Hi, 
Below is a link to my version of bwidgets color.tcl.
It allows named tk colors to be input into the Bwidget color selection dialog.
Perhaps it'll be useful. I've tried to handle errors, but perhaps there are things i've overlooked.
Cheers, Steven
https://sourceforge.net/projects/scidvspc/files/support%20files/bwidget_custom_color.tcl.gz/download

Alternate solution merged with commit [b0d8a1c23c]. RFE closed. Thanks for all, Harald

Thank you for the observation and the patch:

proc SelectColor::_set_hue_sat {hue sat} {
     variable _widget
+    variable _hsv
 
+    set _hsv [lreplace $_hsv 0 1 $hue $sat]
     set x [expr {$hue*200-9}]
     set y [expr {(1-$sat)*200-9}]
     $_widget(chs) coords target $x $y
     _draw_values $hue $sat
}

Please allow me to propose an alternate solution in commit [8acfd06d90]. This bug is also present in the main widget. It was fixed there. Thanks for the bug report.

Thank you, Harald

Your solution seems very nice, cheers. But i can see a hiccup which i   fixed in my version.  To reproduce, open color dialog, type in a new color (eg red), then slide the far-right gradient slider. The colored box is not correct. Attached below is my hack/fix. Cheers, Steven

Hi Steven, thank you for the contribution.

It is now in branch [4f9a4205-named-colors] starting with commit [2605c8c3e2].

We need some fine tuning. Will come up with a version to test.

Thanks again, Harald

Hi Steven,

would the solution in commit [9616d6dea2] of branch [4f9a4205-named-colors-alt] also fit your needs?

It works a bit like an alternate input method. If you enter "red" or "#abc" and press tab, you get the #rrggbb version in the input field. The application always gets #rrggbb back.

To conserve the color name, we would need more work.

Thank you for all, Harald

Hi Steven,
thank you for the contribution.

It is now in branch [4f9a4205-named-colors] starting with commit [2605c8c3e2].

We need some fine tuning. Will come up with a version to test.

Thanks again,
Harald