GPS Recorder: invalid Date of Track

Could you open the Chrome dev console when connected, type Puck.debug=3 in it and then open the GPS recorder downloader and paste what gets printed here?

Sure. Here's the complete response from the console:

Puck.debug=3
3
puck.js:371 <BLE> Sending "\u0010(function() {\n "
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "   for (var n=0;"
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "n<36;n++) {\n    "
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "  var f = requir"
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "e(\"Storage\").ope"
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "n(\".gpsrc\"+n.toS"
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "tring(36),\"r\");\n"
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "      var l = f."
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "readLine();\n    "
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "  if (l!==undefi"
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "ned)\n        Blu"
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "etooth.println(n"
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "+\",\"+l.trim());\n"
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Sending "    }\n  })()\n"
puck.js:371 <BLE> Sent
puck.js:371 <BLE> Received "21,1613468828000,50."
puck.js:371 <BLE> Received "261702,19.054179,306"
puck.js:371 <BLE> Received ".4\r\n"
puck.js:371 <BLE> Received "22,1613748890000,50."
puck.js:371 <BLE> Received "259493,19.052839,254"
puck.js:371 <BLE> Received ".2\r\n"
puck.js:371 <BLE> Received "23,1613914821000,50."
puck.js:371 <BLE> Received "262469,19.054682,256"
puck.js:371 <BLE> Received "\r\n"
puck.js:371 <BLE> Received "24,1614008040000,50."
puck.js:371 <BLE> Received "263432,19.053135,270"
puck.js:371 <BLE> Received ".5\r\n"
puck.js:371 <BLE> Received "25,1614182126000,50."
puck.js:371 <BLE> Received "259883,19.038182,248"
puck.js:371 <BLE> Received ".8\r\n"
puck.js:371 <BLE> Received "26,1614272826000,50."
puck.js:371 <BLE> Received "261817,19.059988,254"
puck.js:371 <BLE> Received ".6\r\n"
puck.js:371 <BLE> Received "27,1614332036000,50."
puck.js:371 <BLE> Received "260909,19.056641,265"
puck.js:371 <BLE> Received "\r\n"
puck.js:371 <BLE> Received "28,1614530565000,50."
puck.js:371 <BLE> Received "259727,19.060739,269"
puck.js:371 <BLE> Received ".6\r\n"
puck.js:371 <BLE> Received "29,1614703251000,50."
puck.js:371 <BLE> Received "259834,19.067476,276"
puck.js:371 <BLE> Received ".3\r\n"
puck.js:371 <BLE> Received "30,1614790117000,50."
puck.js:371 <BLE> Received "259776,19.056448,253"
puck.js:371 <BLE> Received ".9\r\n"