How many UDFs can be added in a SBO table?

Hi all, I have problems:

1. with adding UDF to Item Master Data table. I haved added 18 UDFs to this table and now we want to add more 35 UDFs, but the system showed errors to not allow.

So my question is what is the maximum number of UDFs that SBO allows? If not, show me another solution!

2. I have developed some add-ons, they are registed to the server and installed well on client machines. But when I start an add-on, SBO system show the errors 'Connection timed-out' and the status in the Add-On Manager is 'Failed' but the add-on still runs well.

Please show me how to solve problems!

Many thanks!