What must I do to get an email reminder if someone answered to my question? I didn't found something in the settings.

Umm, not sure there's anything you can do at this time to make that happen as you want it to.

What you might try is to check the little "This is my favorite topic" box, so it always appears in your "My favourite topics" section of the forum. Makes it a whole lot easier to find your original thread.

There is no setting to get an e-mail reminder for the forum, but if someone quotes you or sends you a PM, you'll get a little flag on the upper right hand corner of your window the next time you visit GOG.com. Sometimes you get an e-mail when someone PM's you, but I've found it to be a bit iffy whether or not an e-mail actually gets sent and when it gets sent. The flags however work, but you have to visit the site to see them.

That flag sometimes doesn't always work for me. The little tiny and unobvious "My Posts" icon will take you to a list of replies and threads you've participated in. I bet if you check the ones you participated in you'll sometimes find replies to your posts that you didn't see before.

Yeah if you have multiple replies to your post in the same thread, the "new replies" thing will only take you to the latest one. So it's possible to miss a few even inside a single thread.