Also, make sure to start a Dungeon map first to get the right-selection of dungeon symbols. Click the New button, choose the map type "Dungeon" and then an appropriate dungeon style. Note that "CC3 Dungeon" is a cut-down style with few symbols, make sure to use "DD3 Dungeon" instead of that.

I've rebuilt the installer once more and re-uploaded it. If anybody with a fresh download still experiences the missing files, please let me know.

I second Remy' suggestion. Symbol Set 2 Bitmap A style is the most photo-realistic we have and would suit such a project probably best.

Hide everything but your WALLS sheet, then use the BREAK command (lower left toolbar) to put a gap in both the room and the cave walls. Then show the other walls again.

Alternatively, load the DD3 Wall Feature symbols (click the DD3 button, then the Wall Feature catalog. Use the "Wall Cutter 10" symbol to cut a gap into your wall. You'll need to do it twice, since there are two walls overlapping at that point.

Edit: Ninja'ed by Sue.

Thanks for the report. The template files are indeed missing from the Humble Bundle collection and I'm fixing the setup here. For anyone not wanting to download the whole thing again, I'm attaching the missing files in a zip file here. Extract them to /Templates/Overland Maps/Wizard/ in your CC3+ program folder if you are missing them.