Htmlarea not working in multilanguage site

Zencart 1.3.8
Polish Beta polish as default
English as second language
Multilanlanguage ez pages
classic template
Internet explore browser.

ADMIN: HTMLarea can work in English but doesn't in Polish, when I select HTMLarea for the very first time Htmlarea shows properly for less than a second then it changes into non 'insert' mode.
Ez pages.php files in classic have all been set on 755 permissions.

I have gone through an hour posts reading and could not find the right answer.

Please advise. Thanks

Maria Claudia:

Zencart 1.3.8
Polish Beta polish as default
English as second language
Multilanlanguage ez pages
classic template
Internet explore browser.

ADMIN: HTMLarea can work in English but doesn't in Polish, when I select HTMLarea for the very first time Htmlarea shows properly for less than a second then it changes into non 'insert' mode.
Ez pages.php files in classic have all been set on 755 permissions.

I have gone through an hour posts reading and could not find the right answer.

Please advise. Thanks

Installed FCKeditor plugin, refreshed cache, admin store reset editor no need to rename admin since it is a site not linked yet and not complete .
Situation even worsened, got:

Not Found

The requested URL /MYZEN/editors/fckeditor/editor/fckeditor.html was not found on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

this error is in Ezpages, in products info form etc. it shows in Firefox and IE as well
Can possibly advise,please?
Thanks