As far as I can see, in order to get a free trial of Newgen OmniScan, you need to request it from its developing company. Since I couldn't find any mention of a license key on the product's website, it's very likely that the code in question was communicated to you via email in the account that you registered with.
In case it's not there, I recommend contacting the company's support department directly using one of the following email addresses:
- firstname.lastname@example.org - for the U.S.
- email@example.com - for Europe.
- firstname.lastname@example.org - for the Middle East and Africa.
- email@example.com - for Asia and the Pacific region.