I released a new version but now I reverted back to v1.5.5b, because v1.5.5b turned out to be actually easier work with.
The new version was an attempt to make it easier to get around the UE4 crash that can occur if you setup skeleton retargeting while you have virtual bones. I removed the virtual bones, setup the retarget manager, then re-added the virtual bones. This solves the crashing, but when you download the new project you end up having to repeat these actions anyway so it’s better to work from v1.5.5b.
So, basically, if UE4 crashes when you attempt to retarget animations, do these steps:
1- double click on the UE4_Mannequin_Skeleton provided
2- on the bone names list on the left, delete the two virtual (blue) bones: VB hand_r and VB hand_l and save the skeleton
3- click on “Retarget Manager”
4- scroll down to Select Rig and select “Humanoid Rig” (if it’s already selected, clear it completely, save the skeleton, then select “Humanoid Rig” again) and save the skeleton (again)
5- re-add the two virtual bones as instructed at the end of the instructions video (VB hand_r is child of the head and targets hand_r and VB hand_l is child of VB hand_r and targets hand_l) and save the skeleton
7- retarget the anims normally