We are aware of this. The problem is that we haven't yet managed to find a small example that allows to easily reproduce and thus debug this (e.g. compiling the compiler triggers this issue as well). My suspicion is that it's depending on the dependencies between the units, so it should essentially be reproducible with empty units that only contain uses-clauses.
The problem with recompilation was not limited to the fact that the entire project is compiled. Critical FPC crashes were found, which occur only if the lib folder in the project is not cleared. So, I prepared a project archive for Lazarus (
https://drive.google.com/file/d/1ukTXpNsIanKkcHLvVc-QuxVgoy_d6hNC/view?usp=sharing), which compiles MSEgui from the source code, and it can do this only ONCE, unless you use the -B parameter for the compiler. If the parameter is missing and the project is compiled again, I will get a set of abundant crashes on Windows (Linux has not been tested yet), as for example in the screenshot. I do not yet know how to write a report about this, and is it worth it, or is this problem also known?