I have a similar problem. My camera is 58 minutes ahead of my GPS. So I get out my calculator and my offset is -0.966666!? This is a really odd way to force people to work. It's disappointing that Adobe hasn't tried to make the track import function more usable. Other geotagging apps manage the offset problem much more elegantly: you enter a time for the GPS and a time for the photos and the software manages the difference.
One decimal place is not enough to accurately retag photos. It really makes the geotag function useless unless the time on your camera and your gps are perfectly synchronized.
I think there is a solution to your problem. In the Library module, select the photo(s) that you need to adjust by a couple of minutes, open the Metadata side panel and click 'Edit Capture Time' next to the Capture Time field. Select 'adjust to a specified date and time' and change the 'minutes' part of the 'corrected time'. This adjustment shift will apply to all the photos that you selected (ie the photos will all change by however many minutes you add or subtract - they don't all end up with an identical capture time!). You could either shift them all back 58 minutes to match your GPS, or add two minutes and then adjust the GPS time using the track log time offset - I guess it depends on whether your camera time is (nearly) correct and GPS is an hour behind (as would be the case in the UK if your camera was on BST and GPS is on GMT/UTC) or if your camera is actually 58 minutes fast.
I hope that helps. I guess I could do the same sort of thing to sort my problem out but I know that my camera time was correct in Nepal and the GPX file is on GMT / UTC, so I'd prefer to adjust using the GPS time offset feature.
It would be great if I could get a response from anyone at Adobe but whilst their support seems to suggest that they're there to help, I've been completely unable to contact anyone either by phone or e-mail. But perhaps that's a topic for another thread...
This one really bugged me too. It seems really sloppy that Adobe has such a useless tool for matching the track log times with the photo time stamps (the time zone offset only works in 10ths of a hour!)
However, I'm happy to report that updating your photo timestamps to match your GPS log precisely is pretty easy (and cool): select all the images in your sequence (^A), then pick the photo of your GPS screen with the time (always shoot the time on your GPS). In Metadata, click the time field for the selected sequence, enter the exact time shown on your GPS and Lightroom will give you the option to update the entire sequence relative to the time you entered. Now the Map module will line up your photos and track precisely.
If you already tried and failed to "auto-tag" your images, you have to remove the old GPS coordinates before Lightroom will let you update them. Just click in the GPS field and delete the value and Lightroom will clear the GPS values from the selected images and you're free to re-apply the tags from your track. Use the Metadata menu to write the GPS data back to the JPEG images before you exit if you plan to use the images in a photogrammetry or mapping application.
Thanks for the tip - it had occurred to me recently that I could adjust the time of each photo to give the additional 0.05 minute offset that I require and then adjust the GPS time offset by 5.7hours, resulting in an overall time shift of 5.75hrs as required for Nepal. However, that does seem like a clumsy set of operations to have to undertake, when presumably Adobe could adjust their GPS tracklog offset feature to allow adjustment of time to two, instead of one, decimal places.
I live in hope of being able to contact Adobe Support about this matter, but so far all attempts to establish how to contact Support have failed.