Well I don't know what other issues there may be, or what CTJ means, so I'll leave that possibility out of it & just say that Omolene is a high energy, (very) high NSC sweetfeed. Effectively junk food. So yes, the feed could be affecting behaviour. Also not feeding little & often, starting with 4 cups per feed rather than one & building up to it, especially with high starch stuff can cause gut problems & discomfort which can cause behavioural probs/changes.
If you need to hardfeed your horse for added calories or such, you need to feed over at least a couple of small feeds daily, and if you're feeding only for nutritional balance, you're better off feeding a quality low dose, low NSC 'ration balancer' type product appropriate for your horse's diet. Oh & still feed it daily at least, if at all possible.