Getting in a pickle

First of all couldn't get it to install, and used a simpler cart in Joomla, but now realise I want the facilities as offered by Hikashop - eventually got it to install, then tried to update it to the latest version, and now get the following at the top of the admin page
"Warning: include_once(/home/equinema/public_html/administrator/components/com_hikashop/types/registration.php) [function.include-once]: failed to open stream: No such file or directory in /home/equinema/public_html/administrator/components/com_hikashop/helpers/helper.php on line 495

Warning: include_once() [function.include]: Failed opening '/home/equinema/public_html/administrator/components/com_hikashop/types/registration.php' for inclusion (include_path='.:/usr/lib/php:/usr/local/lib/php') in /home/equinema/public_html/administrator/components/com_hikashop/helpers/helper.php on line 495

Also there's no sign whatsoever of the payment modules (before or after the update)- just a blank space in the control panel - am on the verge of giving up! - help!

You say you have a blank space in the control panel ? Do you mean in the plugins tab ?
That means that the plugins couldn't be installed properly. There must be a problem with the way you installed.

Could you try to download the package again from our website: www.hikashop.com/en/component/doc/ctrl-u...e/task-download.html
Make sure that your plugins folder, among other folders, has correct access rights. Otherwise joomla cannot copy the files at the good place which might be why you have those problems : www.hikashop.com/en/support/documentation/59.html#errors
Then, try to install via FTP like explained on the link above.

The payment plugins should be found in the HikaShop menu System->Payment methods. If you don't have them, it means that the install didn't work properly.

Let us now how it goes.

tried all that, including the ftp method, when I run the install, I get "-1 - An error has occurred.Copy failed"
It's got rid of the error messages, and seems to say I have the latest version, but still no payment modules..........

one thing I have noticed is that noone seems to "own" many of the Hikashop files..........

The "-1 - An error has occurred.Copy failed" error is because of access rights issues on your website. It's not something related to HikaShop but to the way your server is configured. It's Joomla which displays this error when it can't copy the files. For example, the same problem with AcyMailing :
www.acyba.com/en/support/forum/2-bug-rep...or-has-occurred.html
Each time I saw this error, it was an access rights issue. Please make sure that your access rights are correct before installing. You might want to ask your hosting company about it.

Thanks for all your kind help - to be frank I've spent more than enough time on this - the other Joomla shops don't have the same problems, so I'll try them instead.......