```python
import numpy as np
from pyscf import gto, scf, fci, lib

# Task 1: Transform FCI wavefunction with respect to orbital rotation/transformation
# Molecule 1
mol1 = gto.M(atom='H 0 0 0; H 0 0 0.74', basis='sto-3g')
mf1 = scf.RHF(mol1).run()
cisolver1 = fci.FCI(mol1, mf1.mo_coeff)
eci1, ci1 = cisolver1.kernel()

# Molecule 2
mol2 = gto.M(atom='H 0 0 0; H 0 0 1.0', basis='sto-3g')
mf2 = scf.RHF(mol2).run()
cisolver2 = fci.FCI(mol2, mf2.mo_coeff)
eci2, ci2 = cisolver2.kernel()

# Transform wavefunction of mol1 to match mol2 orbital space
mo1_to_mo2 = np.dot(mf1.mo_coeff.T, mf2.mo_coeff)
ci1_transformed = fci.addons.transform_ci(ci1, mo1_to_mo2, cisolver1.norb, cisolver1.nelec)

# Task 2: Transfer FCI wavefunction from a smaller orbital space to a larger one
# Smaller molecule
mol_small = gto.M(atom='H 0 0 0; H 0 0 0.74', basis='sto-3g')
mf_small = scf.RHF(mol_small).run()
cisolver_small = fci.FCI(mol_small, mf_small.mo_coeff)
eci_small, ci_small = cisolver_small.kernel()

# Larger molecule (larger basis set)
mol_large = gto.M(atom='H 0 0 0; H 0 0 0.74', basis='6-31g')
mf_large = scf.RHF(mol_large).run()
cisolver_large = fci.FCI(mol_large, mf_large.mo_coeff)
eci_large, ci_large = cisolver_large.kernel()

# Expand wavefunction to larger orbital space
norb_small = mf_small.mo_coeff.shape[1]
norb_large = mf_large.mo_coeff.shape[1]
ci_expanded = fci.addons.enlarge_space(ci_small, norb_small, norb_large, cisolver_small.nelec)

# Compare the transformed wavefunction with the one obtained from the FCI solver
print("Are the transformed and directly computed wavefunctions close?",
      np.allclose(ci1_transformed, ci2, atol=1e-5))

# Transform the FCI wavefunction using a different method and compare
# For simplicity, we'll use a random unitary matrix as a different transformation method
random_unitary = lib.param.RAND_UNITARY(norb_large)
ci_transformed_different = fci.addons.transform_ci(ci_expanded, random_unitary, norb_large, cisolver_small.nelec)
print("Are the differently transformed wavefunctions close?",
      np.allclose(ci_transformed_different, ci_large, atol=1e-5))
```