Texture studio is somewhat buggy if you're using the newer version, I had a ton of issues at first. I'll list some other commands below for you to test, you may be using an old version as some commands didn't work at first until the creator updated it for my version at least, I had to reinstall it a few times, e.g in my current version /skin and a few others don't work, but nothing that prevents me from mapping. Try updating to the newest version. I've uploaded mine for you in a zip, you can try and use it instead of yours, may work.
https://www.dropbox.com/s/9jl3ijma8agyl55/texturestudio.zip?dl=0
/cobject
/dobject
/sel
/loadmap
/flymode