I do not think Waterfall was updated for RW 8, and you probably had FormLoom 3 installed and need to get FL 4.
To remove Waterfall, hit cancel on this box and then go to RapidWeaver 8 in the menu and down to Reveal Addons Folder
That will open a finder window, find the Waterfall plugin in that folder and delete it. RW will now update themes by itself so you do not need it anyways.
First off, you might want to change the title of the post. Not Dreamweaver but RapidWeaver.
It looks like you might have updated to Catalina?
Have a look at this post.
That worked. Thanks. My old laptop is no longer up to many of the tasks I perform every day.and have switched to a powerful new iMac. I highly recommend them. The problem has been transferring software from one machine to the other,which causes a problem with licence keys. I no longer have some of the older invoices. An example of that is that I can’t find my license key for Stacks 3, and therefore cannot install the Stacks 4 upgrade I bought.
Contact Yourhead support about that, you can get there here:
I am sure they will be willing to look that up for you.
If you know the email address you bought Stacks3 with, you can look up the serial number here https://yourhead.zendesk.com/hc/en-us/articles/228020807
Thanks. Apparently someone from Yourhead saw this post and I found rthe old serial number in my email inbox this morning. Rapidweaver developers are the best!