Hey guys! I'm just dipping my hands into IE modding, but I wrote a small patch to fix the issue @CajunAzn reported (and two other issues I reported on flamewing's GitHub).
To summarize, the reason this is happening is that BG:EE's baldur.bcs is not getting patched with the code that handles the global variables set when the "Release Familiar" ability is used.
The installer looks for the block of code in the file [oldfam.baf] to replace with the code in [newfam.baf]. But the replacement search fails because one line in BG2:EE's baldur.bcs
MoveGlobalObject("fampsd",Player1) // Pseudo-dragon
is changed in BG:EE's baldur.bcs to
MoveGlobalObject("fampsd",Player1) // Pseudo Dragon
Yes, it's weird that REPLACE_BCS_BLOCK will care what the value of the comment string is, but by patching the .tp2 and adding a new variable %pseudo% to [oldfam.baf], I was able to fix it.
MoveGlobalObject("fampsd",%famsummoner%) // %pseudo%
Here's a link to the patch:
https://github.com/flamewing/WTPFamiliars/files/9079650/wtpfamiliars-bgeepatch.zip
Happy gaming!