Running asuswrt 3004.388.8_4 on RT-AX86U_PRO current entware zerotier-one 1.14.0 crashes with a segmentation fault within seconds of starting. I have another RT-AX86U_PRO running a slightly earlier asuswrt version running zerotier 1.12.2 just fine. Here is dmesg log if it helps:
potentially unexpected fatal signal 11.
CPU: 1 PID: 11588 Comm: zerotier-one Tainted: P O 4.19.183 #1
Hardware name: RTAX86U_PRO (DT)
pstate: a0000000 (NzCv daif -PAN -UAO)
pc : 0000007fa2c7414c
lr : 0000007fa2c6bffc
sp : 0000007fa275a970
x29: 0000007fa275a970 x28: 000000001354fce0
x27: 0000007f9c005ce8 x26: 0000007fa2c740c0
x25: 0000007fa2ff5a10 x24: 0000000000000001
x23: 0000000000000024 x22: 0000000055505551
x21: 0000007f9c005ce8 x20: ffffffffa275a400
x19: 000000000000000d x18: 711c30a4ae7493e9
x17: 0000007fa2c27e30 x16: 00000000005ad940
x15: 0000007f9c0002d0 x14: 0ffffffffa275a3e
x13: 0000000000000028 x12: 0101010101010101
x11: 7f7f7f7f7f7f7f7f x10: fefefefefefefeff
x9 : 7f7f7f7f7f7f7f7f x8 : 8080808080808080
x7 : 0000000000808080 x6 : 8080800000000000
x5 : ffffffffffffffff x4 : fffffffff7c5f951
x3 : 0000000055505550 x2 : ffffffffa275a3f3
x1 : 0000000000000000 x0 : 000000005550555e