i don't know if i can explain clearly but any help is greatly appreciated. i'm designing a mechanism by module. which is first i create assembly of pneumatic cylinders consisting of 2 parts with slider connections. everything goes well in the module level. but when i assemble this module into the main assembly, i lost some of the joint axis and drivers in the module. i have the structure of the model tree below. module-assembly works fine but i lost the joint axis of cylinder1 in the main assembly. can aynone explain why is this happening?
main-assembly
-parent part
--module-assembly
---cylinder1
----cylinder-body1
----cylinder-shaft1 ()
---part1 ()
---cylinder2
----cylinder-body2
----cylinder-shaft2 ()
-cylinder
main-assembly
-parent part
--module-assembly
---cylinder1
----cylinder-body1
----cylinder-shaft1 ()
---part1 ()
---cylinder2
----cylinder-body2
----cylinder-shaft2 ()
-cylinder