Well, I tried to dig the issue some more, here's the log part regarding it:
Code:
item Staff of Storms casting autospell Storm (cr0)
Autospell is Storm
castspell: cnr744 spl288 (Storm) vis0 x6 y24 spldmg1
vis 0 xvis -1
blastsqr: unr17146 x6 y24 aoe0 dmg1 eff81 spc1073741824 as10247 al9
affectvic vic17146 hv0
hitunit 17146 17146 dmg1 spec1073741824 ba2
Enchantment
*** Warning: out of ench
hitunit: out of ench
setupsquads end (check=241433822)
It tells us about some mysterious "out of ench", which most likely means there is some limit to simultaneous enchantments. However, as we both know Pan made a good job of capturing most of our scouts with his insane PD, so we both moved to using dozens of stone spheres to have scouting info. And, this scouting is actually considered as enchantment by dom3 engine (I think so because it gives anchntment icon during the battle in scouted province). So, most probably, if we continue to use the stone spheres as we do now, we can throw the game as it clearly makes no sense to fight against 10000 Ermorian armies without BF enchantments (of course absence of Rigor Mortis and Darkness is nice and all that, but still it makes no sense to me).