If you have the free version then you are prohibited from using the C2 product to generate money.
Here is a quote from the manual:
[quote:x72lwokc]Construct 2 Free Edition
Construct 2 can be downloaded and installed to any computer for free, including site-wide at non-commercial institutions like schools. Without a license, it runs as the Free Edition. This has the following limitations:
A maximum of 100 events in a project
A maximum of 4 layers in any layout
A maximum of 2 effects in a project
No folder organisation in the project bar
No event search
No configurations bar
No Families
No Preview on LAN
Not allowed to be used for commercial purposes (however, it can be used in education and other non-profit organisations)