Version Information

Valhesia 3 pre5 1.6.3 modpack
Forge version: 34.1.42
Botania version: 1.6.3-409
Immersive Engineering version: 1.16.3-4.1.1-127

Setup is like so:

• Mana spreader with messenger lens
• Mana prism right above it with celebratory lens
• Button next to spreader
• Redstone wire connector attached to the bottom of the spreader on Output mode
• Redstone wire connector on input mode next to a button (on the floor), linked up to the other connector

When I press the button next to the spreader, the spreader works as expected, all lens perform expected behaviour.

When I press the button attached to the connector, the spreader does not use any of the lens. It's as if they weren't there.

Curiously, moving the prism one block up fixes the problem when it passes through the prism. It even seems to use the messenger lens.

Cannot reproduce the redstone connector issue in 1.20.1 with the corresponding (Neo)Forge version of Immersive Engineering.
It should also be noted that Mana Prism blocks are disabled while receiving a redstone signal. That prism in the last screenshot looks like it would be powered by that lever.

Closing, since 1.16 is no longer supported and this seems fixed in recent versions, or was caused by an unidentified third mod.

Upgraded to Valhesia 3.1.1 I'm having issues with mana spreaders blatantly ignoring lens in other scenarios too. The prism has a gravity+influence lens and the spreader has a messenger lens. When I stuck it onto a timer it worked fine but then I dispensed an item into the prism and the lens stopped working. Normally the beam turns white when it passes through the beam.

EDIT: problem fixed after breaking and replacing the prism