You are still able to race horses who are trained in other disciplines than XC or eventing if you swap their training right before. This is being exploited on days with wet track conditions especially because horses trained in dressage can have maxed out dressage and only be considered a level 5 or so racer.

People who win the mega race, particularly on wet condition days are doing this basically every time and making thousands off of unsuspecting players.

The races level horses off of their XC training level right now. This could probably be fixed if it went off of their highest training level instead.

Example: Horses who are level 10 dressage will be considered level 10 racers despite having level 5XC or level 7 eventing.

This has been fixed. Cross Country now needs to be a higher level or equal to the other disciplines of the horse.