Custom Templates from Client

I am having a hard time converting a client-supplied PowerPoint slide design into a SL template. The file is in PPTX format (PowerPoint 2013). I have tried opening Storyline on my laptop (a 32-bit machine) and importing the PPTX file and then using the Design tab, Save Current Theme As, and giving it a new name.

I then close that run of Storyline, and start a new project. I double click my first slide and go to Design and Browse for Themes and click the theme I just saved.  All I get is a white slide, no background graphics, etc.

Second, when I tried doing this on my desktop (a 64 bit machine) the PPTX file won't even load and I see in the link to the background help file that PPT 2013 64-bit is not supported by Storyline yet.

So here are two questions:  (1) How do I convert the client's slide template into an ahtml file? (2) When will SL be compatible with 64-bit machines?

Thanks!