You have posted to the Tips & Tricks Sub-forum, which is a repository for articles on how to do things in Premiere.
I will Move your post to the main forum, where you will get many more viewers for your problem, and many more suggestions, very quickly. Your link and any e-mail subscriptions will follow along perfectly.
Have you updated your OS to Windows 8.1 with all its patches and updates?
Also, is the Windows 8 on your computer its original factory installation or did you upgrade it from Windows 7 or another Windows OS?
BTW, in my books I recommend that you NEVER open a project created with an older version of the software with a newer version of the program. Premiere Elements 12 will NOT open a Premiere Elements 9 file successfully in most cases and may actually corrupt the .prel file and make it unusabled.
I have not updated to Win8.1 yet , but my Win8 is fully updated with all the patches
Win 8 is from the factory, not upgraded from Win7.
Lastly, thank you for the advice - will not try this again .
I have seen this dvacore.dll type message mentioned online.
I suspect it would be in your best interests to contact Adobe on this serious installation matter as soon as possible.
To do that open the following link, click on "I still need help." to bring up the Adobe Chat pop up.
I have pre-set 2 in the link for "Downloading, installing, and Setting Up".
I do not know if this will involve replacing the dvacore.dll and would prefer to have Adobe make the call on that.
I am currently running Premiere Elements 12 on Windows 8 and 8.1 64 bit without issues.
Please update us on your progress.
Meantime I very much do recommend you get the free Windows 8.1 upgrade. As far as performance, I think it's one of the best things Microsoft has ever done!
Contacting them right now, thank you!
I did do the Windows 8 to 8.1 64 bit "upgrade". Right now I would not agree with you "...it's one of the best things Microsoft has ever done!" Its trying to slip in Microsoft Account in place of Local Account is particularly disturbing. And it is tricky avoiding that happening to you even in a custom setup to 8.1. Even now with my Local Account with Administrative Privileges, every time I get anywhere near one of the apps, up comes the pop to switch to Microsoft Account.
I am not really seeing a big difference between 8 and 8.1 and still favor 7. But, for what we are all here for, Premiere Elements, the performance of the programs remain the same.
Not video editing related, but Win8.1 did NOT work on my wife's computer with an ATI graphics adapter... the driver was made "obsolete" by 8.1 and ATI is no longer providing updates (that I could find) for her model
I had to roll her computer back to Win8 - http://forums.adobe.com/thread/1318710