Hey bro, yeah, exactly! The issue occurs because the system temporarily checks if the summon is dead while its level and attributes are being updated (which happens before it gets revived by the summoning system). If the summon died in a previous battle, this check identifies it as dead and queues it for immediate removal instead of updating its stats and loading it onto the screen.
To fix this, I added just two lines of code: one to revive the summon before applying any level or attribute changes, and then another to heal it so its HP matches the new maximum value.
This way, it should load without issues, even if it died in a previous battle.
Please download the version 4.6 file again; the fix is included and should work without requiring any further changes.