Prior to installing the tablet within BricsCAD make sure it is properly installed at Windows level. After installing the tablet the pointing device has to work: the cursor on screen should react to puck movements on the tablet. If the pointing device does not work yet, this is an install problem at the Windows level and it has nothing to do with BricsCAD. Installation of the tablet in Windows can be problematic. Very few tablets have plug&play installers.
Once the tablet works in Windows, we can configure it in BricsCAD. The tablet menus are customizable via the cui file(s). The tablet menus are not included in the standard 'default.cui' configuration. You have to add the tablet-menu-cui file that corresponds with your tablet overlay layout. Tablet cui-files and printable overlay files can be downloaded from the BricsCAD website here.
The tablet-menu cui file of your choice can be activated by loading it as partial cui file, either with the 'cuiload' command (first browse for the cui file, then click 'Load') or with the 'customize' command (select 'Load partial' from File menu in the Customize dialog).
The tablet has two modes:
Menu mode (tablet OFF), with a little workspace for coordinate input. This requires running the Configure option, possibly retaining default values if your tablet is 12" by 12.
Configure is necessary to access the tablet menus from the cui file. After you configure (_tablet;_cfg) you can see the menu commands in the task bar as you move the mouse over the tablet. Moving the mouse over the white coordinate input workspace makes the tablet cursor work like a mouse, so you can access all menus and tools on screen.
I would start by using configure and checking if the tablet menu works.
Coordinate input mode (tablet ON): uses the complete tablet for coordinates. Tablet ON starts calibration. You can also start calibrate command instead. The calibration asks for a tablet coordinate (no cursor on screen) and a screen coordinate (cursor shows on screen) alternately. If the calibration command runs successfully the tablet mode will be on afterwards. If it does not run well, the tablet has to be configured again to see the menus again. There could be initialization problems if the switching between modes does not go well. If you set the tablet to on for the first time, calibration starts and asks for tablet coordinates. If the switch on failed, it's not possible to enter the tablet coordinates, except if the mouse is in the little workspace. Please check this workspace.
In that case I would try different sequences:
Start by running Tablet ConFiGure.
Try Tablet CALibrate instead of Tablet ON.
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