Make sure you are using at least blender version 3.1.

Make sure you don't have inverted normals on your object (in Edit Mode: select all > Shift+N)

Long droplets work on flat surfaces only for now, very experimental, work in progress.

Enable "realize instances"

Enable "realize instances" before you go into Render preview

Enable "realize instances" before applying the modifier

Make sure you select your weightmap under "Weight Map" option (click on the cross like symbol and select it from the dropdown menu)

Apply the scale and/or rotation of your object (Ctrl + A)

Disable "Long Droplets" (if you don't need them) or increase its count slightly, increase "Big Droplets" count and/or play slightly with the scale/density under "Distribution"

Make sure you apply the scale of your object (Ctrl + A).

2 solutions:

• enable "droplets only", duplicate base mesh and remove the dropletgen modifier of the second copy.

OR

• in your material editor, add a new "Attribute" node, type in "UVMap" and connect it to the vector socket of your texture.