So after I've repeatedly been asked for compatibility between my transformable tails mod and lazybones New Transformations mod and trying unsuccessfully to make my mod compatible with his, I tried doing it the other way 'round and it works.
I won't release modified versions of his skills without his express permission though, so I'll just dump a tutorial here on how to do it yourselves.

SSJ4 and other transformations, that include a tail:

1. Download XenoXMLConverter
2. Go to "[XV2Dir]\data\chara\HUM\" and search for the transformations bust file (for lazybones SSJ4 this will be "HUM_256_Bust.emd")
   
3. Drag'n'drop the busts emd file over XenoXMLConverter.exe
4. Open the resulting .xml in a text editor
5. Search for <EMDSubmesh name="tail">
6. Delete everything from <EMDSubmesh name="tail"> to </EMDSubmesh>, including both mentioned lines
7. Save xml
8. Drag'n'drop xml over XenoXMLConverter.exe

Lazybones New Transformations 3.0+ (transformations that do not include tail): No longer needed, but retained for completeness' sake

1. Uninstall the transformation you want to make compatible, including its BCS entry.
2. Extract the transformations x2m with any archiving program that supports zip (I'd recommend 7zip).
3. Go to the folder where you extracted the x2m. Inside you will find a folder called "COSTUME_ATACHMENT" and inside that there will be a .x2m file. Right click it and choose "Edit".
4. Navigate to the HUM/SYM tab and, in every PartSet, replace
     <Part idx="1">
       <!--Face_forehead-->
       <MODEL value="xxx" />
       <MODEL2 value="xxx" />
       <TEXTURE value="2" />
       <U_10 value="0x0" />
       <U_18 value="0x0" />
       <U_1C value="0x0" />
       <U_20 value="0x0" />
       <F_24 value="0.0" />
       <F_28 value="0.0" />
       <U_2C value="0x0" />
       <U_30 value="0x0" />
       <NAME value="HUM" />
       <!--MODEL, EMM, EMB, EAN-->
       <FILES value="NULL, NULL, HUM_000_Face_base, HUM000U.fce" />
   </Part>
   (where "xxx" is a number between 238 and 270) with
      <Part idx="1">
       <!--Face_forehead-->
       <!--This entry is empty.-->
   </Part>
   if it exists.
5. Do the same in the HUF/SYF tab.
6. Save the file, overwriting the original and close XV2 Costume Creator.
7. Go back to where the transformations x2m is located, right click it and select "Edit".
8. Navigate to the Transformation tab, and select the first custom entry¹.
9. Modify "Behaviour 11", ""Behaviour 10" and ""Behaviour 13" to read 24.
10. Modify "Bcs hair color" and "Bcs eyes color" to the colors you want that transformation to have.²
11. Repeat steps 9 and 10 for every subsequent entry.
12. Go to the BCS tab, click "Set" and in the window that opens, select the x2m that you modified in steps 3-6. In the dialog box select "Embed".
13. Save the file, overwriting the original and close XV2 Skill Creator.
14. Install the modified skill x2m.

If you use any of the BCS patches in lazybones download, you will have to do steps 4-6 with the patch x2m instead and then install it.

This will make the skill compatible not only with my mod, but every other transformable accessory that uses hair colors, such as RazeDevastators Wrapped Saiyan Tails.
As an added bonus it makes it a lot easier to customize the hair and eye colors to your liking.

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¹ By this I mean not SSJ1, 2 or 3.
Basically the first one with a "Behaviour 11" value greater than 2.

² Click on "Get from" and select either "From HUM.bcs" or "From HUF.bcs", does not matter, both should be the same.
For reference, DIMPS' SSGSS skill uses "Bcs hair color" 60.
Some of my personal preferences as a starting point:
Stage Hair Eyes
SSG 8 9
SSB 60 62
SSBK 60 62
SSBKX10 60 62
UI 1 5
SSR 97 5