Why has renaming in scenes been impossible since Update 4.0.2?

Since I updated to Unreal 4 Version 4.0.2 today, I have no chance to rename anything in my Scenes. Let me explain it:
The general Function of renaming works properly, but here’s the big problem:

If I choose a name with an “s” in it, or a “p” in it, the Game-Mode starts. In Version 4.0.1 renaming worked as ever but since 4.0.2 it made impossible to choose good naming convention for assets within the Engine.
As an Example:
Works: norm_xxx
Doesn’t work: BP_xxx (Or Blueprint_xxx)

This is just a no-go. Please help me with this incidence. I would also try a workaround since it is fixed, I just need to work properly again with naming conventions and renaming things.

Doesn’t happen to me, just updated… are you sure you don’t have sticky-keys or similar accessibility on?

Hello,
Thank you for your report. We were not able to investigate this on the engine version you reported, but there have been many version changes to UE4 since this question was first posted. With a new version of the Engine comes new fixes and it is possible that this issue has changed or may no longer occur. Due to timetable of when this issue was first posted, we are marking this post as resolved for tracking purposes.
If you are still experiencing the issue you reported in the current engine version, then please respond to this message with additional information and we will investigate as soon as possible. If you are experiencing a similar, but different issue at this time, please submit a new report for it.
Thank you.