I have the same problem (still running at 100%) and I tried using 2019.4 but it did not change anything. I have student license.
At first I thought it is insufficient computational power (RAM, CPU etc. )problem so I made design space a small section and made target mass to 99%. It reached 100% completed in 10 minutes but I waited 12 hours after that and it did not finish. So it looks like it completed the job but it cannot display it. I dont have any idea what is the problem. I am planning to take a blind shots to solve the problem:
-use different version (2017.1 maybe)
-use different computer (can we use the same license on another computer?)
-change the imported file type (I import the files from Solidworks in .sldprt format maybe change to .step)
Is there anyone that could solve the problem?