Applying coupon to a manufacturer

Is it possible to apply a coupon to be specific to a manufacturer?

If so - how?

If not - please add it in.

Not yet, as of AwoCoupon Pro 1.0.1. The next version will have this function.

will purchasers of previous versions have to buy the new version, is there a free update or what?

As indicated on the product's page, you have free updates for up to 1 year. If you look in your account at the file, it shows you when it expires. So no, you would not have to buy the new version.