Hello.
The Property Sensor brings wrong Results in many Cases.
Example:
P1 = 0
P2 = 0
Sensor: P1 equal P2 -> False
Sensor: P1 not equal P2 -> True
or:
P1 = Timer 0.0
P2 = 3.0
Sensor: P1 greater P2 -> immediately True (with invert -> never True)
Sensor: P1 less P2 -> never True
Also Interval Mode, maybe more.
Thank You for helping.
Regards, Doc
Edit ..........
Also 0.2.3. it seems.
If I'm not wrong, it was never possible to use a property name in the Property sensor's _Value_ field, only literal values (like 3.0, as in the given example file), it's not a bug, it's simply a non-existing feature. If you need to compare two properties, try using the Expression controller.

Actually it seems a limitation in upbge as the code was changed.
I'd have a potential fix for this specific case:
but if we want to fix everything, this would need some work. And I'm not totally sure neither about my patch then it would need panzergame or lordloki review. I think upbge development is paused/stopped then I guess it is better to use workarounds with expressions or other systems...
Thank You. I afraid UpBGE has stopped. But as long this Site exists, i'll report a Bug if i find one. Maybe a Dev is bored some Day and want to do something nice. I'll keep Fingers crossed. :)
As this is not a bug, but more a limitation (or maybe the old bge devs just replaced the old behaviour in property sensor with the expression controller), I close this task
Most helpful comment
If I'm not wrong, it was never possible to use a property name in the Property sensor's _Value_ field, only literal values (like 3.0, as in the given example file), it's not a bug, it's simply a non-existing feature. If you need to compare two properties, try using the Expression controller.