I got a recumbent about 4 weeks ago. It took 15 minutes to get out of the driveway. At first I just sit on the bike with the feet on the pedals and keeping balance by taking hold of a bench in the garage. So I just sat to get a feel of it for at least 5 minutes. Then I pushed forward to exit the garage and get on the driveway.

Then I got off the bike and removed the car from the driveway ;-)

Going like this back and forth, from the garage to the edge of the sidewalk, only sliding, I finally started to crank the pedals and stopped after the sidewalk. Did that several times. Then I went past the sidewalk and onto the street while actually pedalling. I got to the corner and stopped and had no idea whatsoever how to get it going again.

I found out that by giving the first turns of the pedals not seated all the way back I can get it going easily. Actually now I can only give half a turn and then take a better position on the seat while the bike keeps going very slowly. It's amazing how slow you can get on such a bike without loosing balance. Quite the contrary of the first impressions I had when I tried it for the first times.

Unless you have physical impairement I do not think any type of 'training wheels' are needed. Only patience will do. And a quiet street.

Cheers.