Now I've been having this problem for months and I can't seem to find a fix for it.
Basically I updated my computer to windows 10 and now i cant seem use Radiant properly.
When I right click drag on the 2D grid it will move me 1000 paces to the direction I drag to.
I'll add some screenshots of a new window I now get.



I select the Project file and everything opens fine its only when I right click drag.
also I have experience with Radiant and I've never had this problem until now.

---

Double Post Merge: October 30, 2015, 03:10:00 pm

---

Don't worry guys I've figured it out, if anyone else is having this problem this is how you fix it.

Find Radiant by going into your root/bin.
Right click and go to properties.
select the compatibility tab and check Disable display on high DPI settings.
Once complete hit apply and it should be working perfectly again.