also based on this
https://github.com/DarkGuardsman/Fluid-Mechanics/issues/45
again, dont know if they are still there

"Unique" Items, like Tinkers Construct Tools can be put into Crates - server crash - turns them into somethin strange, a block with a rainbow texture.

Bags from different Mods (Forestry for example) will also loose the Inventory in a Crate

Crafting: Filled Crates can be used in "upgrade recipes" (Basic - Advanced - Elite), but loose also all Items in the process.
Also: would it be possible to implement some kind of "Upgrade Item", like the Dimensional Upgrade for Barrels or the Iron Chest items?
And: maybe small optical differences between the crates (like colored corners)?

Texture differences are planned but i'm not in the cosmetic phase of the new mod updates.
Upgrade items are planned but their a bit down the todo list after fixing the armbot up, and working on the conveyor belts.

Not sure whats up with unique items but i'll check it next chance i get. Might have to go back to preventing the use of NBTTagged items from being placed into chests. NBTTag being how items save stuff like inventories, and enchantments.

Crafting i will need to code a special recipe handler for in order to prevent that. It will take some time but i won't be working on it right away. For the same reasons as the upgrade items.

Added texture difs to crates