I don't know much about such options. From what I read this morning, it appears the tax treatment of them can be complex. My guess is that you'll want to use special receipts to set up the scheduled receipts and that you'll have to do the math or make assumptions on the side about the value of such receipts.

I will ask Mike if he has ideas here.

Yes, non-qualified stock options (NSO) are significantly different than incentive stock options (ISO).
The exercise of an NSO is a taxable event; the bargain element, i.e. the difference between the market price and the exercise price, is taxed as ordinary income when the option is exercised.

PLEASE SEE THE 02/15/2015 POST BELOW FOR THE BEST WAY TO MODEL NSOs.

IGNORE THIS - I would model the exercise price as a non-taxable special expense and the bargain element as a taxable special receipt. I would then enter the market price to my regular asset account balance.

Yes, entering the bargain element as part of employee wages is best!
This way the NSO income will be properly subjected to both payroll and income taxes.
All of the tax categories for special expenses and special receipts apply only to income taxes, not payroll taxes.
Sorry for the confusion. I deleted some of my confusing posts.