Scheduled Transactions data archive

[Mke C.]

I started trying to use GnuCash several weeks ago by transferring over 
15 years of Quicken data and finally got most of it sorted out.  I am 
impressed with the alternatives in GnuCash and am still leaning.  
Initially the double entry system and ability to download financial data 
without buying a new program every 2 years was my reason for changing 
but now I see a lot of other benefits. Thanks to all those that 
contribute to improving this program.
1.)  My problem now with scheduled transactions.  I have a number of 
bonds that pay interest on a regular basis and then mature.  I can 
schedule the interest payment OK but cannot schedule the sale.  It 
handles everything except the number of shares.  When it executes, the 
price per share is $1 and the number of shares is adjusted to reflect 
the correct total dollars but this messes up the asset account leaving a 
negative balance.  Is this the only alternative or have I missed 
something?  I can always just enter the transaction at a future date if 
this is a limitation.
2.)  My second question is deleting scheduled transactions.  I deleted 
the entries on the transaction template but can't delete the name from 
the transaction list.  After a while this is going to be a long list 
with entries that have executed and those that are just mistakes.  Is 
there a way to delete them?
3.)  I am trying to minimize the number of accounts and entries I have 
to sort through for past investments that I no longer have.  I have set 
the filter to not show hidden accounts but they still show up in other 
places.  Can I delete the security in the Security Editor without 
affecting the past financial data and will this delete it also from the 
Edit Account>Security/currency>Select>Security list.  I don't want to 
delete something and find it has corrupted all the past history. 
4.)  My data file is about 18M which takes a long time to load at 
startup and to generate reports.  Is there a way to archive past history 
and still retain the basis and lot data for securities that are still 
held to minimize the file size.  I saw in the documentation that you 
could export the file and start a new year with the same account names 
but there was no information on what was retained except the account names.

Thanks for your help,
Mike