John,
Your best bet is 100% neatsfoot oil, not the compound, if you are not looking to replace the straps, and like Tartan Hiker said, use just a little as a little goes a long way. You can also get a product from Tandy/ Leather Factory called Hide Rejuvinator (sp?) that will work on dry leather. Unless it is just surface cracking, the best thing to do is replace the straps with new leather.
As for dye, I would suggest Fiebing's Oil Dye for a professional finish.

Regards,

Brian Woodyard
Owner, Blue Dragon Leathers