I have found this list, which is from Deluxe Paint II. Its most likely very similar to the other versions.
[Technique]
F1 - Paint
F2 - Single Colour
F3 - Replace
F4 - Smear
F5 - Shade
F6 - Cycle
F7 - Smooth
M - Colour Cycle
[Brush]
B - Restore
O - Outline
h - Halve brush size
H - Double brush size
x - Flip brush on X axis
X - Double brush size on X axis only
y - Flip on Y
Y - Double on Y
z - Rotate brush 90 degrees
Z - Strech
[Stencil]
` - Stencil On
[Miscellaneous]
F9 - Info Bar
F10 - Selection Bar
@o - Co-Ordinates
@a - Anti-alias
@r - Colourise
@t - Translucent
TAB - Colour Cycle
[Picture]
L - Load
S - Save
j - Page to Spare(Flip)
J - Page to Spare(Copy)
V - View Page
Q - Quit
[General Keys]
m - Magnify
< - Zoom In
> - Zoom Out
[ - Palette Colour Up
] - Palette Colour Down
( - Palette Colour Left
) - Palette Colour Right
, - Eye Dropper
. - Pixel / Brush Toggle
/ - Symmetry
| - Co-Ordinates
INS - Perspective Control
+/- - Brush Size (Fine Control)
w - Unfilled Polygon
W - Filled Polygon
e - Unfilled Ellipse
E - Filled Ellipse
r - Unfilled Rectangle
R - Filled Rectangle
t - Type/text tool
a - Select Font
u/U - Undo
d - Brush
D - Filled Non-Uniform Polygon
f/F - Fill Options
g/G - Grid
h/H - Brush Size (Coarse Control)
K - Clear
c - Unfilled Circle
C - Filled Circle
v - Line
b - Scissor Select and Toggle
B - Brush
{,} - Toggle between two background colours
I think what I will do, is create a shortcut key ini file where the user is free to change any shortcut key for the functions/tools within the program. That would be the most flexible way of dealing with it, as it will allow anyone to pick what they like best.