1. Yes.
2. You can see a preview, but you can't edit it (unless it's manually written content). You can exclude specific forums from the list, but you can't exclude individual topics.
3. No.
1. I'm working on this, but no ETA yet.
2. No. The plain text template IS going to look terrible, and it will be used in a very small number of situations. Most email clients by now are able to read and format HTML... in fact, I may remove plain-text altogether (since it's so obsolete). And no, you can't add URLs, that's the point of plain text. 😉
3. Not at this time.
I am going to work on this, but no ETA. If you don't hear from me by end of this week, please PM me to remind me. Thanks.
A new version has been uploaded to the Marketplace. It contains a fix for these issues.