From what I know, there isn't a straight forward option for changing the FOV.
I am not sure what the default setting is. I may guess 75 since the original software was released for 4:3 resolutions.
As for changing it, the only way I know of is through scripting.
A script can me made easily with notepad. I know this isn't the script thread but...
Paste that little bit into a notepad document and replace the "#" with a number. Save the document as an "Filename".fpi file and throw it in the scriptbank folder so you can find it easily.
It seems that the value for the "camfov" command is just increasing the default engine FOV by that value.
Example: IF the default FOV is 75 (not sure though) then camfov=15 should change the ingame fov to 100.
To use the script, just replace the main script of a trigger zone and place that anywhere in the level. The player does not need to walk through it for this script to work.
I hope this helps!
In the docs folder,in the main FPS creator directory, a community made guide called "ocfpscguide.pdf" has a wonderful guide to scripting if you're not familiar with it. I'm no expert for sure, but that guide in combination of this community has taught me so much about FPSC. Also, these forums are a great place to ask for assistance. I know it's been a little quiet lately, but there are still a few experts/veterans floating around.
Oh, and welcome to the forums!