Fix common problems

Symptom	Check
Missing assets or modules	Enable TUNS and Niagara, show Plugin Content and check search filters and engine version.
No baked points	Check LOD 0 triangles and the UV channel. Temporarily remove the mask; black or rejected values provide no locations.
Tiny masked region fails	Check UVs and threshold. Broaden the allowed region or reduce bank size.
GPU bake fails	Read Status and Output Log. Confirm rendering and a working RHI/shader target. There is no silent CPU fallback.
Niagara rejects the bake	Rebake after changes; rebuild combined destinations; check Is Ready.
Invisible particles	Check GPU Compute Sim, Surface, spawn count, lifetime, visible material/size and fixed bounds.
Dots are inside the static mesh	Match Niagara position, rotation and scale. Attachment without inheriting scale can put every point inside the visible mesh.
Skeletal preview works but Play fails	Check Attach Parent, the actual Skeletal Mesh Component, matching topology and Whole Mesh LOD 0.
Particles stay behind during animation	Spawn samples once. Add the same TUNS_SampleSkeletalMesh module in Particle Update to keep particles attached.
Offset only affects editor dots	Point Surface Offset is preview-only; use Niagara NormalOffset.
Extra particles overlap	Counts above bank capacity reuse positions. Increase the bank or reduce particles.
Gray mask does not reduce count	Gray affects density weight. Change Niagara’s spawn count.
Source missing in Combine picker	Check mesh, UV channel, readiness, self references, duplicates and cycles.

For a useful bug report, include engine version, RHI/shader target, Status, mesh type, mask settings and relevant Output Log lines. Reproduce with one bake and one emitter first.

Return to the first-effect walkthrough for a known small setup.