Re: Here is the screenshot you requested
There isn't one.
Re: As you can see it is very large
I can't see the numbers, but...
Your describing overall sluggishness of the app's UI is consistent with that.
Mail server issues would only slow down mail sync, but won't affect e.g. just the opening of a message list.
And since "Didn't change much after I compacted the db":
Then please check the "messages to sync" / "messages to cache" settings, the defaults are "25 or 50" and "250" respectively.
Re: how do I send spam messages to my spam folder on the ISP server
You can set your spam folders, in AquaMail, to "Spam, don't sync".
This will still keep the "move to spam" buttons / icons, but those folders won't sync all the time.