There's a long thread on this issue: thread149-64619
I believe that, out of the box, your Crystal Reports Developer will enable to you to build a web app for 50 users, 5 of them concurrent. A 6th concurrent user will fail to access the web app successfully.
The "50 users" part of the license is sort of vague (people come and go from organizations).
Brian J. Alves
Email: brian.alves@worldnet.att.net
VB / ASP / Crystal / SQLServer