Normally I made my custom command with FlywithLua, it works with most add-ons pretty smoothly, but somehow IXEG 737 seems have some coflect between it.
What I find is as soon as I use dataref command to announce a read/write on ixeg dataref, it can't be controlled by ixeg itself (or other conflicts), I actually bump into this years ago as this:
As soon as I have " dataref("IX3_ENG1S", "ixeg/733/engine/eng1_start_act", "writable") " without any other lines, ixeg will no longer able to cutout that switch by itself.
Recently I got another lua to set QNH :
https://forums.x-plane.org/index.php?/files/file/90402-lua-barometer-setting-script/
It have dataref for "sim/cockpit2/gauges/actuators/barometer_setting_in_hg_pilot" and copilot, as soon as these line are here, the auto sync pilot/copilot function in IXEG 737 would no longer works.
Both these problem can be resolved by add my own lua function to achive what the ixeg system should do then, but recetly I build some new hardware and I try to use it for control IXEG's master caution buttons, however, when I have the line of:
dataref("IX3_FIREB", "ixeg/733/firewarning/fire_bell_co_cp_act", "writable")
dataref("IX3_MACU", "ixeg/733/caution/caution_reset_act", "writable")
dataref("IX3_MARC", "ixeg/733/caution/caution_recall_act", "writable")
As soon as this been active, these button would make click sound constantly, and the master caution reset button will also change tilt constantly.
Weirdly, although fire bell and system annciator will have click sound, they actually can be controlled by my code and would not click away information without my command, even with constant annoying click sound...
I have use this style of fwl code for many kinds of 3rd party add-on aircraft they all works great, so this is quite unique to IXEG. Use dataref tool to active these function seems not having problem, I imaging maybe something else like spad.next would work fine? but at least I can't get it works with FWL, so maybe you can take a look at this issue.