How do I save a waveform from ModelSim for later opening/viewing
You need to save the waveform/dataset as a .wlf file.  To tell Modelsim to capture all signal values in the design you can do a log -r /*.  Afterwards you can open up the specific waveform/dataset .wlf either through the GUI or by typing vsim -view &lt;some_name&gt;.wlf in the console.  Have a look in the ModelSim/QuestaSim user manual under 'Saving a Simulation to a WLF File'