I would think 60 employees must generate a lot of unnecessary costs due to computer downtime in addition to whatever costs they are incurring for your time, and that would justify the cost of getting the maintenance contract paid to date.
Unfortunately, a solid Macola installation requires money. If you let the maintenance contract lapse your only alternative is to play hacker and try to get whatever kludge your stuck with to work. As an independent contractor, I avoid customers in this predicament, as I find most of them are bootlegging whatever they can and are spend more time trying to get whatever crap they have to work than is worth the effort, and when it doesn't work all the IT guys get the blame. Most importantly it seems to be these guys who stiff me or go broke just when the invoice comes due. A word of caution: feeling sorry for a company going broke usually results in feeling sorry for yourself later after you go broke trying to help them. It's one of those cosmic rules that has no explanation, like when you loan a friend a car, they always wreck it, or when you loan money to your best friend, you lose a friend and the money.
On your other points, as far as Novell goes, I'd junk the 10 year old turkey you are trying to make fly and put in a W2K server setup. You can usually do a conversion on a 60 user network for less than 10 grand.
On the alternatives to Macola, upgrading your current set up to be up to date is going to cost you the least amount of money. Alternatives to Macola for manufacturers are Great Plains and Syspro at the top of the list, and a few others. It will cost you 10 times as much to convert to them as it would to update your current system.