Sounds like a potential source of the problem to me. I doubt that there is a rubber hose drain line for the hydraulics on the roadster's top. I don't own a roadster, so others that do can chime in on whether there is a drain line for the hydraulics.

For drainage to be occurring that feels "oily", possibly fuel treatment additive that spilled during pour into gas tank. Or possibly a gas tank cap not fully seated or unable to seat when tightened (e.g., defective gas cap). I'd start checking along these lines before I decided to pursue having the top's hydraulics serviced. Sunsetseeker - Do you use fuel treatment additive in your XFire?