Extra line of input was entered into the VPUMP.DAT file found here; \HES\HydraCAD\Ver50\Programs\3DFTGS Unhandled Exception Insert Pump n/a

No error, pump just doesn't insert 

Revit could not complete the external command... Name contains illegal characters

Discharge and or Suction inputs were typed in and not entered via the pull down. input new pump

Pump is in water supply but no reference point PI

Command Failure for External Command... ...System.IO.DirectoryNotFoundException

Revit could not complete the external command.... Details: Name must be unique... At HCAD_Revit_Tools.CAD3.Insert_Pump.Go

Runtime Error 62: Input past end of file

After running an update to 50.54, user is getting this error when trying to add a fitting by right-clicking the fittings cell, a dialog box pops up saying,  May happen with Pipe Schedule and adding a Pump as well.

File to load paths and Dirs.(AND STRING CONVERSION)
CommandLine... yadda yadda yadda

When inserting a listing tag on a pipe, you get the error, "Invalid color number"

Trying to insert a fabricated pipe via HydraLIST doesn't show any outlets, ski poles, etc.

As shown in HydraLIST;

Inserted into HydraCAD;

Note, no GOL is shown.

When selecting Valve Selector in the 3D Fittings window, you get the error message;

SOURCE: System.Private.CoreLib

MESSAGE: An item with the same key has already been added. Key:

When trying to insert a valve type fitting from the parts tree, you get the error; 

Still!!! Block ### is missing.  Please insert manually.

However checking the database for the drawing file shows it exists.

When attempting to Select Sprinkler (SS or SSP command), you get the error;

Point or option keyword required.

Specify insertion point or [Basepoint/Scale/X/Y/Z/Rotate/Explode/REpeat]:

Specify rotation angle <0>:

Then your sprinkler definition box will want to be inserted, rotated and each value set individually

When inserting a vertical pipe, the circle part of the block remains as a white circle, instead of a red pacman/clamshell.

When inserting a vertical pipe/riser nipple with a fraction in the diameter you get atypical results

The fonts for fraction symbols ¼ (quarter), ½ (half), or ¾ (three-quarters) are replaced with ?.840, ?1.050, and ?1.660

When trying to insert a Hydraulic demand block (Compact/Standard/Expanded) (IHD command) and after selecting the .WXF file to use;

You get the error message;

Error: bad argument type: numberp: DATAFILE

And the command kicks you out.

When trying to insert a specific fitting, you get the error

Could not add this part to the fitting because of missing endprep

then;

AutoCAD Error Aborting

INTERNAL ERROR: !dbentapi.cpp@719: eNullObjectld

When you insert your vertical pipe/riser nipple, you see the text "HCAD/D_UNITS" as the diameter's suffix

Error in MiscFunc.exe|PumpCalc|Form_Activate

Error 457-This key is already associated with an element of this collection

The error may also be a Runtime Error instead