Unfortunately, this is likely the case. I am surprised Zonkie doesn't have the same problems with Vanilla after a few hours of play. With only 2GB of RAM you really have none extra to share around. If there was even a minor memory leak in lite it would be enough to push her/his memory requirements over the edge.Sadly I'm guessing that transparent ui bug is a memory issue for low memory computers that in order to get rid off I would probably have to cut the mod into nothingness pretty much. I personally have never experienced it. I could of course make further cuts to the lite version, but for now I'm waiting on more feedback, I guess Wiz implemented lite for CK2+, if he wants more cuts I'll make them.
As for the memory constraints, if Wiz wanted to make the >2GB fix mandatory he should never have a problem using the regular version either. To be honest, I would prefer CK2Plus to not use the lite-version as it is missing a lot of the quality and efforts of your work.