Got the general design solidified and installed. Still working on trimming the Great Stuff before applying the silicone and background mix.
I'm pretty happy w/ the dimension I've been able to create, but I don't think I'll know if I'm happy until the background is complete and planted.
I created a "cave" on the upper level to provide some hiding space, but this created a bit of a problem. While peeling off the outer layers of the foam, I found a pretty significant gap inside the cave that probably would've amounted to a dart frog death trap (or at least an area that would be impossible for me to access). Because of this, I've added a good amount of Great Stuff to the cavity and I'll have to redo it tomorrow. I think this should solve the issue.
I'm going to be out of town this weekend, so I'm hoping to get the background fully completed by then to give the silicone plenty of time to cure before I begin planting.
Sadly, the plants are looking even worse. I think one of the ferns and the sheet moss will make it, but everything is probably a loss. Going to place a new plant order this week; I wanted a few additions anyway, so I'll just order a bit more than intended. (Keeping everything planted though; I've seen some miraculous recoveries in the past, so who knows...)
Additional foam still needs to cure...