Unable to build firmware from sourcecode

Hello folks,
I’ve been trying to modify the twonky nav-tree in my WD MyCloud gen2, which as far as i know, the only way to do this is to modify the twonky install in the source code and build your own fw.

Whenever i follow the steps in the source code relase notes file, i get the following error:

:~/Desktop/mycloud/WD_MyCloud_GPL_v2.31.204_20191206/firmware/merge$ ./merge
kernel name = uImage
firmware name = WD-NAS-firmware
size of structure = 128
default path=…/module/crfs/default/config.xml
Product ID = 0
Custom ID = 14
Model ID = 2
Hardware ID = 1
Sub ID = 1

Make firmware error
Error , Ramdisk sizes too small , maybe your ramdisk is error!

I have ubuntu 16.04 x32 installed in a VM (Hyper-V Win 10)

Any help is appreciated.