There's currently no way to import existing templates into Better Proposals, as the formats of traditional documents simply aren't compatible.
In short, attempting this would probably end up in
a) expenditure of a lot of time and effort and
b) a resulting mess, which goes against our No. 1 golden rule at Better Proposals: documents sent to clients must always look incredible!
It's simple and easy to create proposals and our editor does all the hard work for you to keep things looking excellent. The simplest way to recreate an existing proposal template is to create pages that represent your sections, copy in your content then add colour/images and style the proposal how you like.
If you require any further assistance with this, just drop us a message in the chat and we'll be happy to advise.