May you try Enemy Race Manager 1.22.2? That should fix the crash.
For removing the creep, you can use the following lua script in game chat. It should remove all creep on all surface/planets.
-- For Zerg - Decorative
/c for i=1, table_size(game.surfaces),1 do game.surfaces[i].destroy_decoratives({name={'creep-decal','creep-decal-transparent'}}) end
-- For Protoss - Decorative
/c for i=1, table_size(game.surfaces),1 do game.surfaces[i].destroy_decoratives({name={'tosscreep-decal'}}) end
-- Sh1nzou's protoss
/c for i=1, table_size(game.surfaces),1 do game.surfaces[i].destroy_decoratives({name={'erm_toss_exp/tosscreep-decal'}}) end
-- Sh1nzou's zerg
/c for i=1, table_size(game.surfaces),1 do game.surfaces[i].destroy_decoratives({name={'erm_zerg_exp/creep-decal','erm_zerg_exp/creep-decal-transparent'}}) end
-- Sh1nzou's terran
/c for i=1, table_size(game.surfaces),1 do game.surfaces[i].destroy_decoratives({name={'erm_terran_exp/creep-decal'}}) end
I can add removing deco when the building destroyed, if the 2.0 expansion doesn't do that.