What operating system are you on? Can you draw a cabinet or does none of the CabWriter features work? Did you do a clean install? That is, did you go to your plugins folder and delete the cabwriter and cutlist_bridge files and folders?
I just downloaded version 0.9.3 from the website and installed it with no problem on a PC. I haven’t tried it on a Mac, but Greg has. So I would normally assume that you have an installation problem, except, you have installed it on three different machines and had the same problem. Perhaps you had a problem in download. Try downloading it again.
By the way, what you download from the website is a .zip file. SO you first have to open that file and extract the .cabwriter_0.9.3_beta_released_1-30-17.rbz file before installing. Also, there is only one .rbz install file because I combined the two programs. So when you do the CabWriter install you should find the Extended Entity Info dialog box under the Window menu.
If you continue to have problems let me know and we can set up a phone call for support or perhaps a network screen session.