I can think of several things:
1. Do you have the proper tire tiedowns? Must have these.
2. Generally speaking, if the towed car extends over 4' behind the taillights on the dolly, you need lights on the back of the toad (depending on your state's lighting requirements-see your vehicle code)
3. You need a checklist to make sure you have properly prepared your dolly and toad for towing. Many, many times, the biggest issue is automatically setting the handbrake after loading the toad on the dolly and forgetting to release it until someone flags you down or you see smoke in your rear mirror.
4. Safety chains. MAKE SURE your chains are adequate to keep your toad from taking off down the road if the tire tiedowns fail. Yeah, I know, small chance of that happening, but........ I found that some dollies have lightweight chains that would part if the weight of the toad was suddenly pulling on them.
I had the toad wired so that when plugged into the MH, the brake lights and turn signals operated from the MH, not the toad. Total cost including installation was around $150. A good investment. Also saved toad battery.
Good Luck.