Trying to decrypt data sent from U2 subroutine in PHP

Question

I am being sent encrypted test data from a U2 system to see if it can be handled and utilised to increase security.

The SUBROUTINE generating the encrypted test data in U2 is:

RESULT=''
ALGORITHM="rc2-cbc"                     ; * 128 bit rc2 algorithm in CBC mode 
MYKEY="23232323" ; * HEX - Actual Key 
IV=   "12121212"               ; * HEX - Initialization Vector 


DATALOC=1                           ; * Data in String 
KEYLOC=1                            ; * Key in String 
ACTION=5                            ; * Base64 encode after encryption 
KEYACTION=1                         ; * KEY_ACTUAL_OPENSSL 
SALT=''                             ; * SALT not used 
RESULTLOC=1                         ; * Result in String RESULT 
OPSTRING = ''

RETURN.CODE=ENCRYPT(ALGORITHM,ACTION,DATASTRING,DATALOC,MYKEY,KEYLOC,KEYACTION,SALT,IV,OPSTRING,RESULTLOC)
RETURN.CODE = OPSTRING

The data being generated and encrypted is:

[RAWDATA] => Array
    (
        [196346] => 05FOAA
        [196347] => 05KI
        [196328] => 99FOZZ16S10
    )
[ENCRYPTED] => Array
    (
        [196346] => e0XB/jyE9ZM=
        [196347] => iaYoHzxYlmM=
        [196328] => BS/YmNtlzI95c9NLpl4JVHLJwI/MO3zJm6FKVqu2tcM=
    )

I am using the same information in PHP using openssl_decrypt:

$encdata = array_value;
$encryptionMethod = ALGORITHM; //"rc2-cbc"
$encryptionKey = MYKEY;//"23232323"
$options = 0;
$iv = IV; //"12121212"

$decryptedMessage = openssl_decrypt( $encdata, $encryptionMethod, $encryptionKey, $options, $iv ); 

Return value: bool(false)

I have tried different combinations of $options and tried encrypting the same data myself and I get different results.

I have to wait 24 hours to get a new file with any changes so I wanted to cover off as many problems as possible.

I have read over the documentation and I feel that the following could potentially be issues:

1. ACTION=5 which I can only find 4 potential options from U2 docs - 1 - Encrypt, 2 - Encrypt, the Base64 encode, 3 - Decrypt, 4 - Base64 decode, then decrypt - Is it as simple as this being wrong? I hope so but want to cover of any other possible problems
2. $encdata - I have tried with OPENSSL_RAW_DATA and 0 which I can't tell because the ACTION=5 which is neither Encrypt OR Encrypt & base64 encode
3. $encryptionMethod - I don't think rc2-cbc is a valid option in PHP on my server but can't say categorically - I have suggested to change this to AES256
4. $encryptionKey - is this ok to be a string of 8 chars? Does it need to be a specific length and does it need to be in binary? (Docs have conflicting info)
5. $iv - same as above - is 8 chars and non-binary ok?

Any other insights before I send this off for overnight updates would be greatly appreciated.

PHP Fiddle with testing: http://phpfiddle.org/main/code/ixax-umq3