I would try a couple of things. First is to create a new directory for your music files and try bringing MQS streaming up with no music files. If it comes up then the issue is likely with one of your music files. While applications shouldn't be sensitive to data issues they almost always are and it is very difficult to test for all data anomalies. If it started with no issue and with no music files then stop MQS, add one or two music files to the new directory and restart MQS. If is starts with no issues then you can add more files on the fly until it breaks. Second approach would be to uninstall, reboot your computer, download a new copy of MQS and try again.
Thanks to Buddahacker & Kiats of responding and helpful suggestions...but they didn't work. So frustrating. The MQS server app starts to open and then closes. Wonder if Steph86 has any thoughts...appreciate his notice & link on the update.
And even with my problem, I have to express to scorpio187: you won't regret. Ultimately, the sound is incredible!