Map - label 'UNKNOWN' and link indicator - color does not change

[jeannin]

Hello
I am testing Zabbix to evaluate a potential deployment and I am a beginner at Zabbix.

I see some strange behaviour, probably due to my misunderstanding of how Zabbix works.
My setup is a linux server with KVM in whitch I implement 2 Virtual Juniper router (VMX)

The zabbix server can monitor the 2 VMX thanks to SNMP
When I create a map, I see the following strange behaviour :
1/ when I add label to my VM1
net.if.in ={{HOST.HOST}:net.if.in[ifHCInOctets.529].avg(1m)}
net.if.in ={vmx1:net.if.in[ifHCInOctets.529].avg(1m)}
I see some time the value but somtime I get 'UNKNOWN'
Any explanation
On the opposite the following work always
{vmx1:net.if.in[ifHCInOctets.529].last()}
2/ When I use the same value "vmx1:net.if.in[ifHCInOctets.529].avg(1m)" for link indicator, very occasionaly it works but in general in if the condition is true the color link does not change

Thank you
Xavier

[jeannin]

Just forgot to mention that I use version 5.0.22 and I cannot change this.
Regards
Xavier