LookUpTable in OpenOrder

Moin,

I try to create an OpenOrder with a lookup tables and a dropdownlist, but the appropriate Textfields aren't showing any values:

[{
	"Version": 1,
	"TemplateType": "OpenTemplate",
	"Id": "0E74efa2-32A5-462C-A3A0-749A81D0B52A",
	"DisplayName": "Global - TestTables",
	"Description": "A form to run a script, which creates all needed folders for a new project",
	"IsManualInteractionRequired":"false",
	"ScriptToExecute": "0.08",
	"LookupTables": [
	
		{
		"Name": "LookupTableCompanyShortForm",
			"Definition": {
				"Type": "LookupTable",
				"LookupTableId": "CompanyShortForm",
				"LookupTable": {
					"Firma1": "F1",
					"Firma2": "F2"
				}
			}
		},
		
		{
		"Name": "LookupTableCompanyOU",
			"Definition": {
				"Type": "LookupTable",
				"LookupTableId": "CompanyOU",
				"LookupTable": {
					"Firma1": "OU=Firma1,DC=Domäne,DC=local",
					"Firma2": "OU=Firma2,DC=Domäne,DC=local",			
				}
			}
		}
	],
	
	"Form": {
		"Type": "Container",
		"Label": "New",
		"Templates": [
		{
			"Key": "Company", 
			"Value": {
				"Type": "DropDownList",
				"Label": "Company",
				"IsRequired": true,
				"Items": [
				{
					"Value":"Firma1",
					"DisplayValue": "Firma GmbH"
				},
				{
					"Value": "Firma2",
					"DisplayValue": "Firma AG"
				}
				],
				"DefaultValue": ""
		   }
		},
		
		{
        "Key": "FirmaShort",
        "Value": {
			"Type": "TextField",
			"Label": "FirmaShort",
			"Description": "",
			"DefaultValue": null,
			"IsRequired": true,
			"IsEnabled": false,
			"isHidden": false,
			"isHiddenFromRequester": false,
			"Constraints": {
				"CreationRule": "<lookup>(companyshortform,{Company})"
			}
		}
		},
		
		{
        "Key": "FirmaDN",
        "Value": {
			"Type": "TextField",
			"Label": "FirmaDN",
			"Description": "",
			"DefaultValue": null,
			"IsRequired": true,
			"IsEnabled": false,
			"isHidden": false,
			"isHiddenFromRequester": false,
			"Constraints": {
				"CreationRule": "<lookup>(CompanyOU,{Company})"
			}
        }
		}	
		]
	}
}]	

Is this even possible, where is my error?

Thx in advanced

Sincerely

HPSAdmin