I have tested that command with my indivudually built rpm. It didn't show the dependencies. It would have, if I had inserted them by hand while building the rpm. It only showed the infos that I entered while building it (version number, download location etc.)
Actually there's not one single package simply called "libqt5" or -"devel". They all have any kind of appendix to their names. And the qt5 ones are quite a lot. zypper se libqt4 Loading repository data... Reading installed packages... S | Name | Summary | Type --+----------------...
You can also find software on http://software.opensuse.org/search

gcc49 should be found there. But I guess a newer version of gcc48 should be enough. Click on "show other versions" to find them. Everything will be installed comfortably with yast automatically.
Zypper is still sort of a stranger to me. I tried zypper se qt4 and zypper se qt5. Maybe I got some more results than needed. And since I had installed lmms-1.3.x before, I guess there is a bunch of packages that came by that way and thus are not listed in my overview. zypper se qt4 Loading reposito...
I have to add, that although libsoundio was listed in the dependencies list on github, i got by without installing it. Indeed I had some trouble with it, too. (just added that to my preceding post, too) I just saw you asking about it on discord, Gps ;) EDIT: you were asking where to download soundio...
It works! Here is what's needed to be done: Download lmms-1.2.0-rc2 from https://github.com/LMMS/lmms/releases (that was the newest version at this time). It's the tar.gz source code listed under "Downloads". Install everything listed under "Dependencies" at this page, including ...
Stop with it! Thank you to both of you for caring, one way or the other. I gave it a try: I installed all the stuff mentioned on this page. Most packages were already installed. Some of them just needed the devel-packages to be added. For a few ones no devel-package was to be found. I found no packa...
Nothing happens.

Can you try to activate your contacts, Gps?
Thanks for goofing. Interesting what might come out of it. I tried it with the full 42.1 version (instead of only replacing the files you mentioned). I was amazed to see at least the VST plugin show up. But as you mentioned, LMMS freezes when adding any VST. I tried mdaPiano and DSK Saxophone. Actua...
I just sent a friendly reminder to the packman crew.