As suggested, I went ahead and edited the US English layout. It passes validation, but MSKLC won't let me build a setup package for some reason. I am going to try installing MSKLC in a Windows 7 VM and try to build the package there.
For anyone who may need it in the future, following is the source file I produced. This isn't tested yet.
KBD CmkAltGr "Colemak Without AltGr"
COPYRIGHT "(c) 2012 Company"
COMPANY "Company"
LOCALENAME "en-US"
LOCALEID "00000409"
VERSION 1.0
SHIFTSTATE
0 //Column 4
1 //Column 5 : Shft
2 //Column 6 : Ctrl
LAYOUT ;an extra '@' at the end is a dead key
//SC VK_ Cap 0 1 2
//-- ---- ---- ---- ---- ----
02 1 0 1 0021 -1 // DIGIT ONE, EXCLAMATION MARK, <none>
03 2 0 2 0040 -1 // DIGIT TWO, COMMERCIAL AT, <none>
04 3 0 3 0023 -1 // DIGIT THREE, NUMBER SIGN, <none>
05 4 0 4 0024 -1 // DIGIT FOUR, DOLLAR SIGN, <none>
06 5 0 5 0025 -1 // DIGIT FIVE, PERCENT SIGN, <none>
07 6 0 6 005e -1 // DIGIT SIX, CIRCUMFLEX ACCENT, <none>
08 7 0 7 0026 -1 // DIGIT SEVEN, AMPERSAND, <none>
09 8 0 8 002a -1 // DIGIT EIGHT, ASTERISK, <none>
0a 9 0 9 0028 -1 // DIGIT NINE, LEFT PARENTHESIS, <none>
0b 0 0 0 0029 -1 // DIGIT ZERO, RIGHT PARENTHESIS, <none>
0c OEM_MINUS 0 002d 005f -1 // HYPHEN-MINUS, LOW LINE, <none>
0d OEM_PLUS 0 003d 002b -1 // EQUALS SIGN, PLUS SIGN, <none>
10 Q 1 q Q -1 // LATIN SMALL LETTER Q, LATIN CAPITAL LETTER Q, <none>
11 W 1 w W -1 // LATIN SMALL LETTER W, LATIN CAPITAL LETTER W, <none>
12 E 1 f F -1 // LATIN SMALL LETTER F, LATIN CAPITAL LETTER F, <none>
13 R 1 p P -1 // LATIN SMALL LETTER P, LATIN CAPITAL LETTER P, <none>
14 T 1 g G -1 // LATIN SMALL LETTER G, LATIN CAPITAL LETTER G, <none>
15 Y 1 j J -1 // LATIN SMALL LETTER J, LATIN CAPITAL LETTER J, <none>
16 U 1 l L -1 // LATIN SMALL LETTER L, LATIN CAPITAL LETTER L, <none>
17 I 1 u U -1 // LATIN SMALL LETTER U, LATIN CAPITAL LETTER U, <none>
18 O 1 y Y -1 // LATIN SMALL LETTER Y, LATIN CAPITAL LETTER Y, <none>
19 P 0 003b 003a -1 // SEMICOLON, COLON, <none>
1a OEM_4 0 005b 007b 001b // LEFT SQUARE BRACKET, LEFT CURLY BRACKET, ESCAPE
1b OEM_6 0 005d 007d 001d // RIGHT SQUARE BRACKET, RIGHT CURLY BRACKET, INFORMATION SEPARATOR THREE
1e A 1 a A -1 // LATIN SMALL LETTER A, LATIN CAPITAL LETTER A, <none>
1f S 1 r R -1 // LATIN SMALL LETTER R, LATIN CAPITAL LETTER R, <none>
20 D 1 s S -1 // LATIN SMALL LETTER S, LATIN CAPITAL LETTER S, <none>
21 F 1 t T -1 // LATIN SMALL LETTER T, LATIN CAPITAL LETTER T, <none>
22 G 1 d D -1 // LATIN SMALL LETTER D, LATIN CAPITAL LETTER D, <none>
23 H 1 h H -1 // LATIN SMALL LETTER H, LATIN CAPITAL LETTER H, <none>
24 J 1 n N -1 // LATIN SMALL LETTER N, LATIN CAPITAL LETTER N, <none>
25 K 1 e E -1 // LATIN SMALL LETTER E, LATIN CAPITAL LETTER E, <none>
26 L 1 i I -1 // LATIN SMALL LETTER I, LATIN CAPITAL LETTER I, <none>
27 OEM_1 1 o O -1 // LATIN SMALL LETTER O, LATIN CAPITAL LETTER O, <none>
28 OEM_7 0 0027 0022 -1 // APOSTROPHE, QUOTATION MARK, <none>
29 OEM_3 0 0060 007e -1 // GRAVE ACCENT, TILDE, <none>
2b OEM_5 0 005c 007c 001c // REVERSE SOLIDUS, VERTICAL LINE, INFORMATION SEPARATOR FOUR
2c Z 1 z Z -1 // LATIN SMALL LETTER Z, LATIN CAPITAL LETTER Z, <none>
2d X 1 x X -1 // LATIN SMALL LETTER X, LATIN CAPITAL LETTER X, <none>
2e C 1 c C -1 // LATIN SMALL LETTER C, LATIN CAPITAL LETTER C, <none>
2f V 1 v V -1 // LATIN SMALL LETTER V, LATIN CAPITAL LETTER V, <none>
30 B 1 b B -1 // LATIN SMALL LETTER B, LATIN CAPITAL LETTER B, <none>
31 N 1 k K -1 // LATIN SMALL LETTER K, LATIN CAPITAL LETTER K, <none>
32 M 1 m M -1 // LATIN SMALL LETTER M, LATIN CAPITAL LETTER M, <none>
33 OEM_COMMA 0 002c 003c -1 // COMMA, LESS-THAN SIGN, <none>
34 OEM_PERIOD 0 002e 003e -1 // FULL STOP, GREATER-THAN SIGN, <none>
35 OEM_2 0 002f 003f -1 // SOLIDUS, QUESTION MARK, <none>
39 SPACE 0 0020 0020 0020 // SPACE, SPACE, SPACE
56 OEM_102 0 005c 007c 001c // REVERSE SOLIDUS, VERTICAL LINE, INFORMATION SEPARATOR FOUR
53 DECIMAL 0 002e 002e -1 // FULL STOP, FULL STOP,
KEYNAME
01 Esc
0e Backspace
0f Tab
1c Enter
1d Ctrl
2a Shift
36 "Right Shift"
37 "Num *"
38 Alt
39 Space
3a "Caps Lock"
3b F1
3c F2
3d F3
3e F4
3f F5
40 F6
41 F7
42 F8
43 F9
44 F10
45 Pause
46 "Scroll Lock"
47 "Num 7"
48 "Num 8"
49 "Num 9"
4a "Num -"
4b "Num 4"
4c "Num 5"
4d "Num 6"
4e "Num +"
4f "Num 1"
50 "Num 2"
51 "Num 3"
52 "Num 0"
53 "Num Del"
54 "Sys Req"
57 F11
58 F12
7c F13
7d F14
7e F15
7f F16
80 F17
81 F18
82 F19
83 F20
84 F21
85 F22
86 F23
87 F24
KEYNAME_EXT
1c "Num Enter"
1d "Right Ctrl"
35 "Num /"
37 "Prnt Scrn"
38 "Right Alt"
45 "Num Lock"
46 Break
47 Home
48 Up
49 "Page Up"
4b Left
4d Right
4f End
50 Down
51 "Page Down"
52 Insert
53 Delete
54 <00>
56 Help
5b "Left Windows"
5c "Right Windows"
5d Application
DESCRIPTIONS
0409 Colemak Without AltGr
LANGUAGENAMES
0409 English (United States)
ENDKBD
