Back to Windows for the rest of today. Any suggestions will be actioned tomorrow morning.
Thanks guys - we must get it licked - could it be anything to do with the Ubuntu Firewall?

Hi Sekerob - sorry it's taken so long to reply, but I'm dependent on technical suport. The firewall is so well hidden I could not find any refernce to it. The linux techies tell me it's there, and the rules are the same as for windows - so they say 'if it works on Windows it will work on Ubuntu' - Well - as you know - it doesnt work. I have gone back to the WCG supported version of Boinc via Synaptic Package Manager, but it's still the same. I'm stumped, and don't know the OS well enough to do anything else. Any chance of someone logging in via NetMeeting?

Sekerob amigo - I feel like a real fool - I cant find the folder in which the boinc files are kept. I do a search for cc_config.xml and it never ends, but is not found. Where must I look?

There's no reason to include the file except if you're overriding one or more of the default settings. It's the same with global_prefs_override.xml and remote_hosts.cfg, they're only present if user overrides something locally on a computer.

OK - found it (it's in /var/lib/boinc-client - cant understand why the search didnt find it). I edited the cc_config.xml to read
<!--
This is the configuration file cc_config.xml of the BOINC core client.
For a complete list of all available options and logging flags and their
meaning see: http://boinc.berkeley.edu/trac/wiki/ClientMessages
-->
<cc_config>
<options>
</options>
<log_flags>
<task>1</task>
<file_xfer>1</file_xfer>
<sched_ops>1</sched_ops>

<cpu_sched>0</cpu_sched>
<cpu_sched_debug>0</cpu_sched_debug>
<rr_simulation>0</rr_simulation>
<debt_debug>0</debt_debug>
<task_debug>0</task_debug>
<work_fetch_debug>0</work_fetch_debug>
<unparsed_xml>0</unparsed_xml>
<state_debug>0</state_debug>
<file_xfer_debug>0</file_xfer_debug>
<sched_op_debug>0</sched_op_debug>
<http_debug>0</http_debug>
<proxy_debug>0</proxy_debug>
<time_debug>0</time_debug>
<http_xfer_debug>0</http_xfer_debug>
<benchmark_debug>0</benchmark_debug>
<poll_debug>0</poll_debug>
<guirpc_debug>0</guirpc_debug>
<scrsave_debug>0</scrsave_debug>
<app_msg_send>0</app_msg_send>
<app_msg_receive>0</app_msg_receive>
<mem_usage_debug>0</mem_usage_debug>
<network_status_debug>0</network_status_debug>
<checkpoint_debug>0</checkpoint_debug>
<file_xfer_debug>1</file_xfer_debug>
<poll_debug>1</poll_debug>
<network_status_debug>1</network_status_debug>
<proxy_debug>1</proxy_debug>
<http_debug>1</http_debug>
<http_xfer_debug>1</http_xfer_debug>
</log_flags>
</cc_config>

You will see the changes at the end.

Now I run boinc manager, and allow new tasks, but nothing downloads. Maybe I have exceeded some allowance? I'll also try to reboot and see what happens.
The log was too big to load into the post and bombed - and I lost the 'copy'. I have exceeded the daily limit and cant load more WUs today. It all happens so fast and the log is enormous.
I'll try again tomorrow - anything we can do to limit the log?