I've been using a total station for levelling for over 30 years. After we started using software for least squares adjustments, I used to convert differential-trig field data manually into the .dat (M5) format using a text editor and that was brutal. That became un-necessary when TBC created the manual level file import, which I greatly appreciated.
These days all of our crews use LevelME, which is an app they sell for Trimble Access. It is a little quirky and I think that its .dat file could use improvement (using project units and inverted rod in particular should be added if it isn't by now), but it works really well. I've been out of the field for about 5 years, so it might have seen more improvements. Also, it creates a file you can import into any software that takes a DiNi file and there is a way to transfer the adjusted run into the .job file, although I never used it for adjustments, so I can't say how well that works.
If you use Trimble Access and want to do trig-differential leveling, LevelMe is a great investment. It has to be far cheaper than creating a macro or some sort of import format. I was pestering Trimble to create this functionality for years and I think that if it could be done with an import format, they would have done so or told me to do it. LevelMe came out probably around 2012-2015.
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Dave Olander
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