Step 6
Layout -> Details (Chronological list)
Set thumbnails amount for thumbpreview:

If you set "Thumb preview for every category contains N thumbanils", Brownie will show N thumbnails for every category every day.
If you split text gallery list into several parts, thumbpreview will be splited as well. So remember, if you have 40 thumbnails in to parts, there will be 20 thumbnails per part.
Important:"Main list contains total" is total links amount include text links and thumbpreview.
Step 7
TGP Brownie thumbpreview help