Вот кое-что из Mailing List по поводу этой проблемы... Во-первых, чтобы выполняющиеся в фоне Actions не замораживались, нужно вызывать Services.actionHook.Step. Во-вторых, есть уже упомянутый Sleep.

The solution to this indeed is to call Services.actionHook.Step during a
timed loop.
This procedure exactly does the stepping of the background tasks
(Services.Actions) and works fine while being called on command level also.
(It should not be called by Actions, however!)
(Well, let me also clarify that this is my understanding of the module
Services and not a documented feature.)

How come you didn't try this yourself after having suggested it in xyBoss3?

Note that by adding such a call in HostPorts.Input followed by a conditional
Kernel.Sleep and having Services.actionHook.Step a little bit more robust
towards calls from anywhere (even Actions) any BB system becomes much more
responsive and won't do any excess CPU heating while tracking the mouse,
e.g. making a text selection

Regards
Marco Ciot