In order to install - will need to enter the code ...

06492-09293-48567-50690-50674

(this code has expired now - so will need to temporarily set the system clock back - May 1997 - is good!)

Alternatively, here is a license code that isn't an expired demo code. It's for version 5.2, but the 5.0 installer on this page recognizes it as valid:
06084-56234-17396-59009-65071
If you use this code, you don't have to mess with setting your system clock back several decades, and you also don't have to apply any cracks. This is very handy for running under SheepShaver.