As you mentioned that Muse crashes after placing a .png, did you try removing it and see if exports go well.
If you still see the crash please share your .muse file with us so that we can investigate and try fixing it.
For sharing the file you can follow the steps explained here - https://forums.adobe.com/docs/DOC-8652 and send the link to me in a private message. (In your case please don't delete any item from the file, and send it as it is)
For doing a private message hover the mouse on my picture and click "message".
Hi there, ankushr40215001
to the point: Go to the CC Desktop Application on your machine and click onto the gear wheel next to your avatar.
unfortunately in my case (macOS High Sierra, Safari 11.0) there is no gear wheel and no entry: creative cloud files... may be they have changed it with the version CC 2018, but then you should know that.
I can send you the muse.file, but then I have to have your valid mail-adress, so I can send it by wetransfer.
waiting for your reply
Not at all an issue, for now take my email ankrao(at)adobe(dot)com.
I have checked your file and found that the issue was with your page settings.
Right-click on the home page > go to properties and select "reseat".
And it should work as it worked at my end.
Also, as a side tip, you should avoid placing a an image frame directly over the slideshow or make sure it falls within the page boundary.
Let me know if this helps.