So apparently if you select your whole map via map properties then shift drag/copy and paste for symmetrical maps it crashes Hammer. However if you select the whole map by doing a box with the selection tool then pressing Enter doesn't crash Hammer.
(I struggled with that for a hour or so...
Waterworks is a symmetrical KoTH map in the Borneo-Process-theme following the Viaduct Formula. It is currently in Alpha.
### LOOKING FOR A MODELER FOR MIRRORING PROPS ###
Its only custom content so far is the Borneo assets pack.
On the Workshop...
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