There's no limit on the abstract length in the database; it uses a "text" type field, which is variously implemented as a blob-like field depending on what database you're using. The most likely cause for a failure is if you're copying and pasting from something like Microsoft Word, which uses "smart quote" characters that are technically non-standard. Was there an error message displayed? If not, could you check the logs for one? That will generally indicate the problem.
We'll likely be incorporating a work-around for smart quotes in the next release.
Open Journal Systems Team
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