When defining a PC with epic spell slots (10+) using Improved Spell Capacity, spells slots are not granted.
When using bahamut epic level handbook source, the spell slots are granted, it's why I report this as a DATA issue.
I've attached a sample wizard built with 3.5 RSRD (epic wizard.pcg)
and a sample druid built with bahamut sources (epic druid.pcg)
I've made a bit of debugging myself, and seen the SPELLCAST bonus does not appears in the PlayerCharacter.bonusManager, despite beeing defined in the lst file.
The druid get this bonus in its PlayerCharacter.bonusManager : SPELLCAST.CLASS.DRUID;LEVEL.10=1.0
Linux & Windows
I’m at a loss, the feats are identical:
Which means it is not the feat with an issue.