SUP 2.1.2 Issues

I'm new o SUP and I'mt trying to create a application to learn something

I read lots of posts and examples and "how to"'s but I got to a point where I need some expert advice or explanation

Here is my example:

I created a bapi in my backend system (only reads the materials –par_matnr, by the movement numbers - par_miscari = bwart and data):

*"  IMPORTING
*"     VALUE(PAR_MATNR) TYPE  ZBAPI_SUP_IMPORT-PAR_MATNR
*"     VALUE(PAR_DATA_LOW) TYPE  ZBAPI_SUP_IMPORT-PAR_DATA_LOW DEFAULT 19000101
*"     VALUE(PAR_DATA_HIGH) TYPE  ZBAPI_SUP_IMPORT-PAR_DATA_HIGH DEFAULT SY-DATUM
*"     VALUE(PAR_MISCARI) TYPE  ZBAPI_SUP_IMPORT-PAR_MISCARI OPTIONAL
*"  EXPORTING
*"     VALUE(RETURN) TYPE  BAPIRETURN
*"  TABLES
*"      PAR_MATNR_DATA STRUCTURE  ZBAPI_SUP_TABLE

Here are my 3 issues:

1. In my MBO's start screen I need to use multiple parameters to send to the MBO. In the examples I've seen they all use only one parameter and only 1 personalization key. In debugger I only saw 1 value passed o the backend system even if I have values for both parameters. Can you shade some light?
2. I need to create some custom Error screens but I didn' find a "how to". In the MBO, I've generated a "standard" error screen for the list and 1 for details but these need to be customized.

The issue here is

1. The code can only be done in JAVA ? Can't I do something in backend system and only pass it to the error screen ?
2. I have the return table and the PAR_MATNR_DATA table as export parameters. I've checked both tables as "output" parameters in the creation of the MBO, but that created a concatenation of fields (i.e. I have the fields from both tables as output fields). I need a logic in the backend system ? Can I use only 1 structure and send either the list of values or the error messages?
3. The above logic is for the Jco but I want to create this also for GW use. I tried to create a backend service after some examples I found on SCN. I've atached one: [Content Deleted Jan 2014]

My problem is when I want to modify the code . The service simply doesn't work. I get a HTTP 500 error, even if the original code creates a usable service. How can I find the problem ?

Thank you

Message was edited by: Jason Lax