Found this thread yesterday as I was stuck in a Holy Trainer 4. I tried a silicone lubricant on the lock (WD40 can irritate skin) with no luck, lock would not budge. However, the excess lubricant got on by balls, and was so slick, I was able to slide them out one at a time. It was not comfortable to say the least, but it solved the problem. Afterwards, I tried using a little screw driver and forcing the lock, used vice drips on the screwdriver for leverage, no luck, the lock metal just shaved off. Then tried drilling out the lock, put it in a vice to hold, and the bit got most of the way through, then it veered off in to the resin. Tried a bigger bit, but could not get the lock to open. Finally went in from the other end of the lock, drilled a hole, and just pushed the lock out of the other side. Patched up the hole with a little epoxy, good as new.