Robert, first things first: As obtuse as it may sound, the end is not nearly as far as it may now seem. The docs originally thought it would be 4 months before I could put weight on my leg/foot, and its moved up an entire month, in (large) part due to the general strength training I've been able to get in on the TRX.
I completely with you on the limited space. So that I was certain to use it, I set the TRX up in my bedroom (wedging the door anchor in the jamb of the closet door - as opposed to simply tossing it over the top and closing the door) which also allowed me to thieve pillows from the bed to make for a softer landing when I would lose my balance and inevitably swing in toward the bed/door. Falling - by the way - was a made significantly "easier" by rotating to my ass and tucking both legs up (this only happened a few times before it ceased being an issue).
As for modified routines, most of the standing upper body exercises could be done from a sitting position (with both feet raised for greater core/balance influence) which helped; and the ab and glute routines had to done either with the injured leg flat on the floor, or (as its ROM improved) simply tucked in the cradle which helped with maintaining movement and muscle memory - though only retarded the atrophy. I recommend the Core Strength and All Body Express DVDs - though at some point I kept hoping for less of that Frasier guy in my daily routine.
Good luck with the recovery - it really will go by quickly.
Carlos