Any options for playing in windowed mode?

Built into the game itself? No.

However there is a program called Dxwnd, that will allow you to play the game in windowed.

1. Download the program and extract it somewhere.
2. Start it up
3. Click "Edit" on the menu and Select "Add"
4. Name it, select the file path to your "Space Colony.exe"
5 Set the Window to the size you're using in game.
6. Click OK.
7. The double click on your newly added Space Colony HD in the list.

You will likely need to tweak heavily with the settings inside of Dxwnd to get it to work. My own settings for the game are:
DirectX Hook: Automatic
Emulation: Primary Surface
Trace->DirectX checked
Surface Handling-> FixTextOutA placement checked
Surface Handling-> Remap GDI Client Rect checked
Gerenric->Optimize CPU Checked
Cursor Handling->Correct Mouse Position (You will need this one regardless I think, mouse off 5 to 10 pixels down in game)
Cursor Handling-> Force Cursor Clipping checked
Cursor Handling-> Keep Cursor within Window checked
Windows Handling- Prevent Win Maximize