If by round you mean the 3rd and 4th digits to the right of the decimal point are 0, then the test whether you've crossed a round number would be INT(100*open)<>INT(100*close), and the test whether you've crosses a half round number would be INT(200*open)<>INT(200*close). Something like
Formula:
=IF(INT(100*open)<>INT(100*close),"Price opens at "&TEXT(open,"0.0000")&" and crosses "&TEXT(ROUND(AVERAGE(open,close),2),"0.0000")&" to close at "&TEXT(close,"0.0000"),
IF(F8<>G8,"Price opens at "&TEXT(open,"0.0000")&" and crosses "&TEXT(ROUND(2*AVERAGE(open,close),2)/2,"0.0000")&" to close at "&TEXT(close,"0.0000"),""))
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