You say "Should" because the Save As funcionality is buggy? I am testing the save as functionality. I like it. I mean, It should work.
Yes, should, because there is no such thing as "Save As" functionality if the IDE has become unstable (possibly even because you crashed your program) and e.g. can not detach or interact with the debugger or clean up threads. Goes for ALL IDE's, not just Lazarus... Usually the files become read-only or get mutilated... But there's always a single back-up.
There are a myriad of reasons why "Save As" does not work anymore. "Save As" is not buggy during normal operations and during the forced bugs I created in by bogus units.
I can't reproduce it with your code. Simply do what I wrote, delete the LPi and open the lpr (which is the main program). That will simply create a new lpi for you... Are you paying attention?