Debbi:
Welcome to Ireland Reaching Out! The only Cloonfree townland in Co. Roscommon is in Cloonfinlough civil parish which is not far from Stokestown.
I has some success finding an 1864 civil birth record for Winifred. The Ryan family lived in Bunnamucka townland in Killukin civil parish. Killukin is the parish to the west of Cloonfinlough. See below.
Finding Martin is more difficult without knowing his parents names. The 1855-1856 Griffiths Valuation head of household listing for Cloonfinlough parish showed two Dempsey records in Cloonfree. One a Margaret and the other a Martin. Margaret was likely a widow. Based on the possibility that this Martin was the father of Martin who went to the USA, I located an 1858 baptismal record in the Strokestown records. That record is below.
The same couple (Martin Dempsey and Bbridget Farrell also had a son Michael born in 1866 who lived in Cloonfree so this may be the correct family for your ancestor. See below.
Roger McDonnell
Name:Winifred RyanDate of Birth:12-Feb-1864
Registration Date:25-Feb-1864Address:BunnamuckaParish/District:STROKESTOWN CIVILGender:FemaleCountyCo. Roscommon
Denomination:Civil Parish
Father:Thomas RyanMother:Winifred McLoughlin
Occupation:Farmer
Sponsor 1 /
Informant 1:Thomas RyanSponsor 2 /
Informant 2:Ng Ng
Name:Martin DempseyDate of Birth:24-Jan-1858
Date of Baptism:1-Jan-0Address:
Parish/District:STROKESTOWNGender:MaleCountyCo. Roscommon
Denomination:Roman Catholic
Father:Martin DempseyMother:Brigid FarrellOccupation:
Sponsor 1 /
Informant 1:Thomas WalshSponsor 2 /
Informant 2:Maria Walsh
Name:Michael DempseyDate of Birth:10-Aug-1866
Date of Baptism:1-Jan-0Address:CloonfreeParish/District:STROKESTOWNGender:MaleCountyCo. Roscommon
Denomination:Roman Catholic
Father:Martin DempseyMother:Brigid FarrellOccupation:
Sponsor 1 /
Informant 1:Edward NearySponsor 2 /
Informant 2:Brigid McLoughlin