Can I force entity regeneration?

Yes. The following code fragment uses RegenMode property to force entity regeneration.

myEntity.RegenMode = regenType.RegenAndCompile; 
viewportLayout1.Entities.Regen();

The same property can be used to force entity compilation only (in this case you need to manually update the entity's bounding box).

// ensures a valid bounding box (usually done by Regen())
myEntity.UpdateBoundingBox();

myEntity.RegenMode = regenType.CompileOnly;
viewportLayout1.Entities.Regen();