> Limits

Plugin-wide

• A C++ project is required. The plugin is compiled with your project.
• UE 5.7 and 5.8 on Win64 are the only built-and-tested combinations, and 5.5 and 5.6 do not compile — see what has been built and tested, release by release.
• Nothing replicates. No entry knows about the network. A loop, a drive or a wait runs where it was started and nowhere else.
• The C++ Flow layer is EXPERIMENTAL and may change shape without a major version bump.
• Game Thread only. Every entry is driven by the world’s tick pass or by the console. Nothing in the plugin is thread-safe; calls from other threads are unsupported.
• The four Flow nodes are placeable on an event graph only, never inside a function graph.
• No content ships. The descriptor allows content; the distribution carries none.

Per entry

USCTickableObject

• Does not root itself; the owner holds it.
• Does not run subclass teardown on garbage collection; only Shutdown() does. A leak is reported, not repaired.
• Cannot be hosted from a Construction Script.
• No catch-up on a throttled interval: a long hitch yields one Tick, not several.

USCConsoleCommandRegistrySubsystem

• Commands execute only while a game world exists — never in the editor outside Play. A command that should act on the editor itself needs an editor subsystem, which this is not.
• One Blueprint child per project, and no C++ subclass in an always-loaded module.
• Unregister a command after it has returned; the console manager makes no promise that unregistering from inside a command’s own execution survives it.
• An empty Owner is rejected, not treated as “everything”.

The loop nodes

• There is no delay after the last iteration; Completed follows it immediately.
• Items Per Tick has no effect with Auto Continue cleared.
• Delay together with Items Per Tick is C++-only.
• No pause options: a paused game runs no iterations.

Do For Duration

• One drive per node object; a second Activate() is ignored.
• The alpha is not clamped when a curve overshoots.
• Cancelling from inside the update: on the C++ core, nothing may touch a capture after the cancelling statement. The node’s Cancel from On Update works today because the node’s handler touches nothing after it — a property of the current code, not a guarantee.

Wait Until

• Condition must be a Blueprint function; an event fails to compile.
• Poll Interval at or above Timeout never polls on a tick; with Check Immediately the condition is asked once, at activation, and then the node times out.
• An unbound or lost condition ends through On Timed Out.

Print String Formatted

• Numbers are culture-formatted; the grouping is unstable and will change.
• Case variants of an argument name share one pin.
• There is no C++ side to this node and nothing to call.

What disappears in Shipping and Test

Why each entry goes, and what still exists of it in the build that drops it: the print node is dropped by the Blueprint compiler, the registry by a preprocessor guard.

One more thing goes from Shipping, and the plugin does not decide it: the engine, by default, compiles logging and ensure out of it, so every message in Diagnostics is absent there too.

Not verified

• Platforms other than Win64, and engine versions newer than UE 5.8 — the dependency list suggests they would work; none has been built. Versions older than 5.7 do not compile, so they are not on this list.

A report confirming or contradicting this is useful: Issues.