P: Map module keeps flashing "map offline" when it's not

Lr 6 should not have the map-offline-problem. If it has, it did not upgrade to the latest version (6.13 currently).

The nice thing about lr5.7 is it is extremely easy to add in more functionality. The map in lightroom isn't that important , more important is being able to select the files for processing which can easily be done.  http://regex.info/blog/lightroom-goodies/gps 
Giving adobe more money because their software is broken doesn't sit well but its relatively easy to work round. If it's real gps coordinates you want to add e.g a gpx track from an android phone or a Garmin unit then the link above is for you.  If you are faking it then open the files in finder and use another application to add the gps locations. 
Exiftool will write anything you need it too. There are a number of projects that use it to actually write to the raw file. 

 https://play.google.com/store/apps/details?id=com.eartoearoak.gpxlogger 

is a very simple logger for gpx on android , simple as start stop and pause.  I go somewhere i start this on my phone and go take photos , most often i'm at home before i remember to turn it off 🙂 but transfer the gpx file to your computer and jeffs gps lightroom plugin will  attach the gps data to your photos and give real world locations too. these can be used at different levels to pull up photos in lightroom e.g ireland would do any irish photo county cork just photos in county cork and you can view in google earth or other maps..

@gavinr
What do you mean with "really expensive"? I bet you'll have a hard time to find a piece of your photo gear that had a lower price tag ... and the software part nowadays is as much a part of a photo-chain as the camera or a lens.

It is because of this arrogance that I left LR for Aftershot pro3. Yes without map module. Pity

I wish the solution was a simple as upgrading to Lightroom 6.
I purchased the upgrade to find that the problem persisted, although it was not as severe. The off line periods were frequent enough to be frustrating, without making the module quite unusable. 
This is disappointing from a well established company like Adobe,

I agree with Sune - I, and I'm sure many others, are still using Lightroom 5.7. When I bought this software - which was really expensive - I planned on using it for at least 3-5 years to make the investment worth it. When I bought it, there was no statement by Adobe that "this software expires in 3 years" -- in fact there was an implicit understanding that it would work as advertised indefinitely. Now I agree that I would not expect the software to work after say 10 or 15 years, but 3 short years?? cmon - Adobe has a responsibility to fix this issue.

Would you believe it, the final Lightroom 5.7.1 release was 3 years ago today, and it's 4 1/2 years since Lightroom 5 was release. I know that doesn't feel like a long time, but in technology terms, it's an eternity.

There is still a discounted upgrade available, if you don't want to move to subscription, and those upgrade fees pay for Lightroom to continue to work with external changes, such as new operating systems and changes on other people's servers.

@Victoria: It is not yet 3 years old, and less then 2.5 when the problem started. How was I to know it was only months from being replaced with version 6 when I bought it... I think is is bad service, but from a selling point is is of course better to get people to by a new product.

Agreed, it is slow. Though faster than re-launching the app.

Oh great!  Thanks for the pointer.  I checked for an update only at the weekend.  I'll try again tonight.  This back and forth between library and map is slow when you're working with a lot of photos