We faced with the problem of changing the Virtual Hardware VM section (CPU/RAM) during the template instantiation. Seems to do all like documentation says but the template instantiates with it's default params of CPU and RAM.
<?xml version="1.0" encoding="UTF-8"?>
<vcloud:RecomposeVAppParams
xmlns:ovf="http://schemas.dmtf.org/ovf/envelope/1"
xmlns:vcloud="http://www.vmware.com/vcloud/v1.5"
powerOn="false">
<vcloud:SourcedItem>
<vcloud:Source href="https://myhost.com/api/vAppTemplate/vm-7498f8b7-09e6-4474-bdc0-50e2b411b790"/>
<vcloud:VmGeneralParams>
<vcloud:Name>NEW-XX8</vcloud:Name>
<vcloud:NeedsCustomization>true</vcloud:NeedsCustomization>
</vcloud:VmGeneralParams>
<vcloud:InstantiationParams>
<ovf:VirtualHardwareSection
xmlns:vssd="http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_VirtualSystemSettingData"
xmlns:rasd="http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData"
xmlns:vmw="http://www.vmware.com/schema/ovf"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
ovf:transport=""
vcloud:type="application/vnd.vmware.vcloud.virtualHardwareSection+xml"
vcloud:href="https://myhost.com/api/vApp/vm-7498f8b7-09e6-4474-bdc0-50e2b411b790/virtualHardwareSection/" >
<ovf:Info>Virtual hardware requirements</ovf:Info>
<ovf:Item>
<rasd:AllocationUnits>byte * 2^20</rasd:AllocationUnits>
<rasd:Description>Memory Size</rasd:Description>
<rasd:ElementName>5120 MB of memory</rasd:ElementName>
<rasd:InstanceID>5</rasd:InstanceID>
<rasd:Reservation>0</rasd:Reservation>
<rasd:ResourceType>4</rasd:ResourceType>
<rasd:VirtualQuantity>5120</rasd:VirtualQuantity>
<rasd:Weight>0</rasd:Weight>
</ovf:Item>
</ovf:VirtualHardwareSection>
</vcloud:InstantiationParams>
</vcloud:SourcedItem>
</vcloud:RecomposeVAppParams>
Would be very pleased for helping..
