"... not praise it."
I think I still have the manual still on my bookshelf for Xtree Gold. Didn't they change something in the Gold version that screwed up the secrete sauce?
Thinking about their UI, back in those early days, I was writing my .COM programs in assembler and later in C. It seems like I had some software from MagnaCarta that allowed me to use the color monitor and get some of those fancy exploding dialog boxes and such. I had a math library from a company called MIX that I used. Both were very low cost for us hobbyists.
Really, thinking back, outside of some of the very early software I don't remember too many problems. I used (still do) FPGAs and when Altera came out with Quartus I was beta testing it. Their applications engineers came for a visit so I could demonstrate that it could not build a simple NAND gate!
We used to use Sun and Apollos and were on the hunt for a better simulator. We went to one of the major software companies to have a look at their tools. I had prepared a schematic just in case they asked us for a circuit, which to my surprise, they did. So they enter my trojan horse and I provide them with some details on how to run it. Core dump! Took down the whole system.
They were upset and of course asked me details about it and I explained how I had simulated that same circuit that day with PSPICE at $3000 a copy. If you played at all with those work stations, you know it wasn't going to be cheap. That may have been Mentor.