3dends folder or files missing unhandled exception

When attempting to Launch HydraLIST to start building your riser, you get this error;

When trying to insert a 3D fitting via the Fittings Parts Tree, the user gets the error message;

Microsoft .NET Framework
Unhandled Exception has occurred...
Argument 'Key' is not a valid value

When user clicks CONTINUE and tries to use the INSERT button to insert a fitting, another dialog box pops up

INSERT FITTINGS
Unhandled Exception...
Index was out of range.  Must be non-negative and less than the size of the collection.  Parameter name: index

Unknown *invalid_ skipole* 3D Risers HydraCAD v50

Raising to 3D and you get this error;

Exception Occured at AddURLToHyperlinks :: HydraHeads

System.Runtime.InteropServices.COMException (0x80040154): Retrieving the

COM class factory for component with CLSID

{44D62FAE-67A7-4131-BF38-489CDFE44738} failed due to the following error:

80040154 Class not registered (Exception from HRESULT: 0x80040154

(REGDB_E_CLASSNOTREG)).

Trying to get an elevation but the results are either 0 or an incorrect value

This result should report 3000mm, instead it reports 230mm

This should report 3000mm, not 0mm

When raising to 3D (S3D command), you get a yellow circle with the message "Takeout of fitting does not match takeout expected for a "??????".  Change fitting of fabrication method"

When closing a drawing in 3D, and later re-opening and returning to 2D, some of the drawing symbols show up looking like outlines (Hangers, Sprinklers, etc)

When raising to 3D, you get the following error;

Error inserting to block table HEAD#/HH## to head dictionary

Sprinkler heads not defined in the drawing or no 3D block assigned for a sprinkler head. Going to Navis only - corrupt Persistent Model drawing? eKeyNotFound Dialog box HydraCAD