After importing the csx from the old BC installation like 7.0, 7.1 and 7.2, the Gateway Server fails to start.  The GS engine times out waiting for a response, and adjusting the GS timeout does not resolve the issue.

Although communication between the interior server and gateway server is happening. You will see the following error in an interior server log file

Error in [Gateway/MSH/Inbound/To-DMZ/Sync-Reply-to-DMZ.process/JMS Queue Requestor] There was an unexpected error while sending a message.

This is caused by the timeout settings between the interior server and gateway server are introduced in BC 7.2.0 HF1. When importing the csx file from an older BC installation, the default value of 3600000 is set under "Application Management -> BusinessConnect ->Configuration >Edit Application Configuration: BusinessConnect > Intercomponent Advanced Settings -DMZ Interior Timeout (seconds)".  This is an invalid value, which causes the "JMS Queue Requestor" process to error out. You can find this value under your old deployment BusinessConnect.dat file located under:
TIBCO_HOME/tra/domain/domain_name/datafiles directory

data/BusinessConnect.dat:    <instanceInfoProperty name="__GLOBAL_SUBSTITUTION_VARIABLE__gatewayProperties/transports/Intercomponent/dmzmsh/shortAckWait" value="3600000"/>
data/BusinessConnect.dat:    <instanceInfoProperty name="__GLOBAL_SUBSTITUTION_VARIABLE__gatewayProperties/transports/Intercomponent/dmzmsh/waitDuration" value="3600000"/>
datafiles/BusinessConnect_root/defaultVars/gatewayProperties/transports/Intercomponent/dmzmsh/defaultVars.substvar:                     <value>3600000</value>
datafiles/BusinessConnect_root/defaultVars/gatewayProperties/transports/Intercomponent/dmzmsh/defaultVars.substvar:                     <value>3600000</value>