Thanks for the feedback here!
You are correct - currently, there is no option to select multiple targets from the history list and add them in multiple new tabs all at once. This is something that I'd be happy to get an enhancement request logged for, though.
Utilizing a workspace (as you mentioned), or even multiple workspaces (if you have different lists of targets) is the best method to accomplish what you're needing here.
If you should ever find yourself needing to load up targets from the history list - there is a keyboard shortcut that does make this process a *bit* quicker. If you press "Ctrl+N" on your keyboard, PingPlotter Pro will open a new tab. From there, you can double click on a target to begin tracing, hit "Ctrl+N" to open another tab, and repeat the process as necessary.
As far as crash you mentioned - if you'd like, please feel free to submit a support ticket directly from PingPlotter ("Help" -> "Email PingPlotter Support"), and we'd be happy to take a look at your error log to see if we can offer any guidance on what happened there!