I’m running out of available storage on my MacBook Pro. Looking at what is in Downloads, I see there are lots of downloaded RapidWeaver stacks files (e.g., SectionsPro.stack, Rails.stack, PopDrop.stack) with the square Lego-like icons. These stacks have already been installed. Can I delete these files in Downloads? I have the same question for RapidWeaver Plugin files (eg., Accordion.rwplugin) and RapidWeaver Theme files (e.g., Forward.rwtheme).
Yes. So long as they have been installed, RapidWeaver keeps them in a different location.
Best to keep a backup of them on an external drive or memory stick just in case you ever need to install again from scratch say in the event of a hard drive failure. Having all your purchased RapidWeaver installers to hand will save having to download everything again from the developers’ sites.
Don’t forget that installers .dmg files often include valuable read me files, snippets and demo projects for that Stack, so it’s worth hanging on to them in case you want to refer to these at a later stage.
Keeping a backup of your RapidWeaver Addons (the location where all your Stacks, themes and plugins are located) folder would also be worthwhile in case of emergencies.