Hi zooroo , Welcome to the Studio forums. You can find the numbers for an object by putting your mouse over one from the recolor object menu:
It shows it in hex, which you can convert either with your computer's calculator or with Studio's hash generator which is available in the tools menu.
If you want to use a custom item that you made, you can find its number in the Warehouse on the Object Definition line:
In your second picture it looks like Studio did not recognize that as an object list so it has the wrong comment. In the next version it will be able to look up those item names but that shouldn't affect your mod.
Please do not PM me with modding questions. Post in the Creator Help forum.
If you are having problems seeing the CAPTCHA, please clear your browser's cache and cookies and ensure that you do not have any browser addons or extensions that interfere with the display of the CAPTCHA. Then, close the CAPTCHA window and click on the register button to open the CAPTCHA again.