parse } error - to be added, indepth tutorial for this one as it can be multiple problems.

map doesn't load (broken error) - means your map is broken, follow the above step to locate if there are any broken brushes.

map is rainbow ingame - you will need to include a light grid and a few reflection probes around your map, caulk box is needed also. there are a few tutorials around for all of these.

certain parts of the map are darker than the rest - ensure that your sunlight direction is not obstructing this, if its meant to be like this and you want the area to be a bit lighter then you can add a 'light' entity.

Max Scene Surfs - Caused by multiple glitched patch layers being ontop of each other, to solve this issue you will need to delete the patch layers. models can also cause this error if the model has too many surfaces on it

server script compile error - this error is thown by the compiler that isn't able to compile code, use developer 1 and reboot your map, then open the console in full (shift + `) to see more details on what and where the error is located, if it states a line number its usually the line above the line stated.

script runtime error - script runtime error is where your script has an infinite loop and has been forced to stop. There are a few other examples that can cause this problem (will list them shortly).

asset limits:

1600 Sound limit - hit max limit, free up some sounds through the mod and associated csv files.

xanim limit - NA

ui limit (itemdefs)[new] - i cannot recall what the actual limit was as i found this limit myself, but i'd say no more than around 300 itemdefs should be used in one menufile.

4096 xmodel limit - hit max limit, free up some models by commenting them out in your mod folder and associated csv files

400 fx limit - hit max limit, free up some fx by commenting them out in your mod folder and associated csv files

128 tags (joints) - caused by AI which has too many joints (exceeds 128 bones error), reduce the amount of bones included in the xmodel export.

2048 material limit - hit max limit, free up some materials by
commenting them out in your mod folder and associated csv files

31 hud element limit - hit max limit, free up some hud elements by
commenting them out in your mod folder and associated csv files,
also checking if too many are drawn in the UI.

ui not showing up - this can be many problems, but the most common
one would be that you have a syntax error. these errors don't
display in the console ingame so you will need to take slow steps
through testing in order to locate the problem. usually caused by
typos or unknown functions.

EXE_ERR_HUNK_ALLOC_FAILED256/Out of memory - close some processes in
windows to free up some ram in order to compile successfully.

"" is bad "type" - an item that doesnt exist in the map but is
being called through script.

Server command overflow/ERR_CLIENT_CMD_OVERFLOW - this happens when
the console spams too many commands in a short period of time,
causing the server to crash. ensure that theres no infinite loops
in your scripts (especially through UI scripting)

Server message overflow - this error is caused by console spam of
messages, which leads to server crash if too many are printed in a
short time. to solve this problem you will need to make sure there
are no infinite loops (or very short time intivals) between the
message and the loop process.

Couldn't load &&1 - the engine couldn't load file/item or entity
etc.. (going to use X to describe them all in one) this can be
solved by checking if X exists and if X is loaded correctly
(precached and included in the mod)

ERR_WRONG_MAP_VERSION_NUM - same as below, where each of you have
different map versions (two different compiles), ensure that you
have the same map version in order to play with eachother

SERVER_IS_DIFFERENT_VER - this error happens when you have a
different version to the server, meaning your assets may have been
modified. this error can occur when you modify a stock iwd aswell.

alien font - To be added

couldn't load image - image either doesn't exist or it's not
precached/included in your mod. ensure that its included in your
mod.csv and your mods 'image' folder.

exceeded maximum number of script strings - this error is caused
when you have too many script string loaded, to solve this problem
you will need to reduce the amount of strings so that the pre-load
doesn't output this error.

unknown item &&1 - unknown item defines that the item (weapon/weapon file) does not exist in your version of the mod, to solve this you will need to ensure that the weapon file is included in your mod.csv and is ticked in the compiler.

Could not open - either the file wasn't precached correctly (in
mod.csv/map.csv/map_patch.csv) or the file simply does not exist,
check syntax if it does to ensure there are no typos.

"some mods don't show in my mod folder?" - your mod's folder may be
overfilled, i'd suggest moving a few to a different folder (or
deleting if needed be), this helps reduce "loaded mod listing"
engine use.

type undefined is not a field object - any object with getent that
doesn't exist in the map when trying to use it through script (i.e.
targetname:thisdoesntexist)

duplicate sound alias file - duplicated sound alias file was located, check mod.csv/map.csv/map_patch.csv to see if you may have added the preached line twice; if not then go to your sound alias folder in raw and see if there's any sould alias files that used the same sound name.

*Crashes upon map load* - reboot exe, enable developer 1 and
logfile 1, boot up map, wait until crash, go to your maps mod
folder, open console.log in a text editor and find any unusual
errors.

*Crashes upon exe load* - close exe, check compiler (both build mod
and map compile dumps should be there (if you didnt clear the feed
and build both the map/mod) and locate any unusual errors towards
the bottom of each map/mod compile dump/

If you have any other errors you would like to suggest then please do so, i'll add them to the list

1600 Sound limit - hit max limit, free up some sounds through the mod and associated csv files.

400 fx limit - hit max limit, free up some fx by commenting them out in your mod folder and associated csv files

server script compile error - this error is caused by a syntax error within your script, use developer 1 and reboot your map, then open the console in full (shift + `) to see more details on what and where the error is located, if it states a line number its usually the line above the line stated.

script runtime error - script runtime error is where your script has an infinite loop and has been forced to stop.

syntax error - a syntax error is where something doesn't exist in the engine, whether its a function or a typo, it must be correct in order for your map to load.

Your script advice(top 3) isn't correct at all.

No, this is error is thrown when the compiler isn't able compile the code. While bad syntax is an example of this, there are other situations.

Again, that is just one example of when you may come across this error. This error is given when code that will compile but does something erroneously while running. 

You are getting confused with "Unknown Function" error. No, Syntax is the structure of the language and what it expects in a piece of code(for examples, brackets after the function header to mark the beginning and end of the function).

Cheers for correcting them, i wasn't too sure myself anyway's so i asked for advice on them through chat, i'll update them now