This routine automates the process of redefining Blocks in the current drawing with ones of the same name that are held on a local disc drive or network folder.

The routine goes through the following process:

1. The user is first prompted to navigate to the folder containing the local copy of the Blocks, select any file in chosen the folder (it does not have to be a .dwg file) and then click Open.
2. The routine then checks each Block in the drawing's Block listing to see if there is a corresponding Block in the selected folder.
3. If a match is found, the file in the folder is used to redefine the corresponding Block in the drawing.

Once complete, it is necessary to re-run the Add / Update Links routine.

Note: if updated Blocks have had insertion points or rotation angles changed compared to the Superseded ones, this process will cause the drawing to change accordingly. As such, Blocks may end up being relocated in seemingly random places and at *whatever* rotation angles: #GoFigure. In such occurrences, please use AutoCAD's UNDO command and contact Elecosoft for further advice and assistance.

1.10 - 17/08/17: Added IconSystem to list of blocks to be ignored
1.09 - 29/03/17: Block download authentication added; minor fix to reporting
1.08 - 21/06/16: Revised to separate specification versions from Block versions
1.07 - 16/06/16: Updated storing and restoring of AutoCAD variables
1.06 - 16/06/16: Added check to see if any Blocks have been coloured by the Block colouring routines, if so the user is prompted: 'Please run the 'Reset Colour' before running this routine again...'
1.05 - 06/06/16: Reworked process for ignoring Blocks. The routine now ignores hatch, xrefs, Block created from bound xrefs, any Block name beginning with an underscore, any Block name beginning with TerminatorO and / or DimBlks
1.04 - 19/05/16: Set to ignore Blocks named: _ARCHTICK, _CLOSED, _CLOSEDBLANK, _NONE, _OBLIQUE, _OPEN, _OPEN90, _ORIGIN, DIMBLK, TERMINATOROPEN or TERMINATOROPEN_0.5
1.03 - 05/05/16: Typo corrected
1.02 - 28/04/16: Timer and Block count added
1.01 - 21/04/16: Results message added
1.00 - 08/04/16: Initial version.