Thanks for the screenshot! It looks like that DPT sentence must be from a very old NMEA 0183 device as an additional parameter was added to that sentence by the NMEA in 2001.
The new Coastal Explorer was created using a (much) newer version of the specification, but we’ll go ahead and make that last parameter optional in the next update.
EDIT: Turns out the newer code does handle the older form of this sentence. The real problem here has to do with the “TAG block” which is the part between the ‘’ characters before the sentence. They appear to be valid in the screenshot, but Coastal Explorer is not “processing” them correctly. This is affecting everything other than the wind speed and angle, not just the depth. Well get this fixed for the next update.